Create files needed to run Jekyll locally

By adding a Gemfile, it is possible to test the website/documentation
rendering locally.  This expects a reasonably recent version of "bundle"
to be installed, and from within the docs directory:

    bundle update
    bundle exec jekyll serve

will run a small web server on port 4000 to preview the docs.

Signed-off-by: David Brown <david.brown@linaro.org>
diff --git a/docs/.gitignore b/docs/.gitignore
new file mode 100644
index 0000000..cf1879a
--- /dev/null
+++ b/docs/.gitignore
@@ -0,0 +1,2 @@
+.sass-cache/
+_site/
diff --git a/docs/Gemfile b/docs/Gemfile
new file mode 100644
index 0000000..047e5e2
--- /dev/null
+++ b/docs/Gemfile
@@ -0,0 +1,27 @@
+source "https://rubygems.org"
+
+# Hello! This is where you manage which Jekyll version is used to run.
+# When you want to use a different version, change it below, save the
+# file and run `bundle install`. Run Jekyll with `bundle exec`, like so:
+#
+#     bundle exec jekyll serve
+#
+# This will help ensure the proper Jekyll version is running.
+# Happy Jekylling!
+gem "jekyll", "3.5.2"
+
+# This is the default theme for new Jekyll sites. You may change this to anything you like.
+# gem "jekyll-theme-cayman", "~> 0.1"
+
+# If you want to use GitHub Pages, remove the "gem "jekyll"" above and
+# uncomment the line below. To upgrade, run `bundle update github-pages`.
+gem "github-pages", group: :jekyll_plugins
+
+# If you have any plugins, put them here!
+# group :jekyll_plugins do
+#    gem "jekyll-feed", "~> 0.6"
+# end
+
+# Windows does not include zoneinfo files, so bundle the tzinfo-data gem
+gem 'tzinfo-data', platforms: [:mingw, :mswin, :x64_mingw, :jruby]
+
diff --git a/docs/Gemfile.lock b/docs/Gemfile.lock
new file mode 100644
index 0000000..4893ee4
--- /dev/null
+++ b/docs/Gemfile.lock
@@ -0,0 +1,220 @@
+GEM
+  remote: https://rubygems.org/
+  specs:
+    activesupport (4.2.8)
+      i18n (~> 0.7)
+      minitest (~> 5.1)
+      thread_safe (~> 0.3, >= 0.3.4)
+      tzinfo (~> 1.1)
+    addressable (2.5.2)
+      public_suffix (>= 2.0.2, < 4.0)
+    coffee-script (2.4.1)
+      coffee-script-source
+      execjs
+    coffee-script-source (1.11.1)
+    colorator (1.1.0)
+    ethon (0.10.1)
+      ffi (>= 1.3.0)
+    execjs (2.7.0)
+    faraday (0.13.1)
+      multipart-post (>= 1.2, < 3)
+    ffi (1.9.18)
+    forwardable-extended (2.6.0)
+    gemoji (3.0.0)
+    github-pages (160)
+      activesupport (= 4.2.8)
+      github-pages-health-check (= 1.3.5)
+      jekyll (= 3.5.2)
+      jekyll-avatar (= 0.5.0)
+      jekyll-coffeescript (= 1.0.2)
+      jekyll-default-layout (= 0.1.4)
+      jekyll-feed (= 0.9.2)
+      jekyll-gist (= 1.4.1)
+      jekyll-github-metadata (= 2.9.3)
+      jekyll-mentions (= 1.2.0)
+      jekyll-optional-front-matter (= 0.2.0)
+      jekyll-paginate (= 1.1.0)
+      jekyll-readme-index (= 0.1.0)
+      jekyll-redirect-from (= 0.12.1)
+      jekyll-relative-links (= 0.4.1)
+      jekyll-sass-converter (= 1.5.0)
+      jekyll-seo-tag (= 2.3.0)
+      jekyll-sitemap (= 1.1.1)
+      jekyll-swiss (= 0.4.0)
+      jekyll-theme-architect (= 0.1.0)
+      jekyll-theme-cayman (= 0.1.0)
+      jekyll-theme-dinky (= 0.1.0)
+      jekyll-theme-hacker (= 0.1.0)
+      jekyll-theme-leap-day (= 0.1.0)
+      jekyll-theme-merlot (= 0.1.0)
+      jekyll-theme-midnight (= 0.1.0)
+      jekyll-theme-minimal (= 0.1.0)
+      jekyll-theme-modernist (= 0.1.0)
+      jekyll-theme-primer (= 0.5.2)
+      jekyll-theme-slate (= 0.1.0)
+      jekyll-theme-tactile (= 0.1.0)
+      jekyll-theme-time-machine (= 0.1.0)
+      jekyll-titles-from-headings (= 0.4.0)
+      jemoji (= 0.8.0)
+      kramdown (= 1.13.2)
+      liquid (= 4.0.0)
+      listen (= 3.0.6)
+      mercenary (~> 0.3)
+      minima (= 2.1.1)
+      rouge (= 1.11.1)
+      terminal-table (~> 1.4)
+    github-pages-health-check (1.3.5)
+      addressable (~> 2.3)
+      net-dns (~> 0.8)
+      octokit (~> 4.0)
+      public_suffix (~> 2.0)
+      typhoeus (~> 0.7)
+    html-pipeline (2.7.0)
+      activesupport (>= 2)
+      nokogiri (>= 1.4)
+    i18n (0.8.6)
+    jekyll (3.5.2)
+      addressable (~> 2.4)
+      colorator (~> 1.0)
+      jekyll-sass-converter (~> 1.0)
+      jekyll-watch (~> 1.1)
+      kramdown (~> 1.3)
+      liquid (~> 4.0)
+      mercenary (~> 0.3.3)
+      pathutil (~> 0.9)
+      rouge (~> 1.7)
+      safe_yaml (~> 1.0)
+    jekyll-avatar (0.5.0)
+      jekyll (~> 3.0)
+    jekyll-coffeescript (1.0.2)
+      coffee-script (~> 2.2)
+      coffee-script-source (~> 1.11.1)
+    jekyll-default-layout (0.1.4)
+      jekyll (~> 3.0)
+    jekyll-feed (0.9.2)
+      jekyll (~> 3.3)
+    jekyll-gist (1.4.1)
+      octokit (~> 4.2)
+    jekyll-github-metadata (2.9.3)
+      jekyll (~> 3.1)
+      octokit (~> 4.0, != 4.4.0)
+    jekyll-mentions (1.2.0)
+      activesupport (~> 4.0)
+      html-pipeline (~> 2.3)
+      jekyll (~> 3.0)
+    jekyll-optional-front-matter (0.2.0)
+      jekyll (~> 3.0)
+    jekyll-paginate (1.1.0)
+    jekyll-readme-index (0.1.0)
+      jekyll (~> 3.0)
+    jekyll-redirect-from (0.12.1)
+      jekyll (~> 3.3)
+    jekyll-relative-links (0.4.1)
+      jekyll (~> 3.3)
+    jekyll-sass-converter (1.5.0)
+      sass (~> 3.4)
+    jekyll-seo-tag (2.3.0)
+      jekyll (~> 3.3)
+    jekyll-sitemap (1.1.1)
+      jekyll (~> 3.3)
+    jekyll-swiss (0.4.0)
+    jekyll-theme-architect (0.1.0)
+      jekyll (~> 3.5)
+      jekyll-seo-tag (~> 2.0)
+    jekyll-theme-cayman (0.1.0)
+      jekyll (~> 3.5)
+      jekyll-seo-tag (~> 2.0)
+    jekyll-theme-dinky (0.1.0)
+      jekyll (~> 3.5)
+      jekyll-seo-tag (~> 2.0)
+    jekyll-theme-hacker (0.1.0)
+      jekyll (~> 3.5)
+      jekyll-seo-tag (~> 2.0)
+    jekyll-theme-leap-day (0.1.0)
+      jekyll (~> 3.5)
+      jekyll-seo-tag (~> 2.0)
+    jekyll-theme-merlot (0.1.0)
+      jekyll (~> 3.5)
+      jekyll-seo-tag (~> 2.0)
+    jekyll-theme-midnight (0.1.0)
+      jekyll (~> 3.5)
+      jekyll-seo-tag (~> 2.0)
+    jekyll-theme-minimal (0.1.0)
+      jekyll (~> 3.5)
+      jekyll-seo-tag (~> 2.0)
+    jekyll-theme-modernist (0.1.0)
+      jekyll (~> 3.5)
+      jekyll-seo-tag (~> 2.0)
+    jekyll-theme-primer (0.5.2)
+      jekyll (~> 3.5)
+      jekyll-github-metadata (~> 2.9)
+      jekyll-seo-tag (~> 2.2)
+    jekyll-theme-slate (0.1.0)
+      jekyll (~> 3.5)
+      jekyll-seo-tag (~> 2.0)
+    jekyll-theme-tactile (0.1.0)
+      jekyll (~> 3.5)
+      jekyll-seo-tag (~> 2.0)
+    jekyll-theme-time-machine (0.1.0)
+      jekyll (~> 3.5)
+      jekyll-seo-tag (~> 2.0)
+    jekyll-titles-from-headings (0.4.0)
+      jekyll (~> 3.3)
+    jekyll-watch (1.5.0)
+      listen (~> 3.0, < 3.1)
+    jemoji (0.8.0)
+      activesupport (~> 4.0)
+      gemoji (~> 3.0)
+      html-pipeline (~> 2.2)
+      jekyll (>= 3.0)
+    kramdown (1.13.2)
+    liquid (4.0.0)
+    listen (3.0.6)
+      rb-fsevent (>= 0.9.3)
+      rb-inotify (>= 0.9.7)
+    mercenary (0.3.6)
+    mini_portile2 (2.2.0)
+    minima (2.1.1)
+      jekyll (~> 3.3)
+    minitest (5.10.3)
+    multipart-post (2.0.0)
+    net-dns (0.8.0)
+    nokogiri (1.8.0)
+      mini_portile2 (~> 2.2.0)
+    octokit (4.7.0)
+      sawyer (~> 0.8.0, >= 0.5.3)
+    pathutil (0.14.0)
+      forwardable-extended (~> 2.6)
+    public_suffix (2.0.5)
+    rb-fsevent (0.10.2)
+    rb-inotify (0.9.10)
+      ffi (>= 0.5.0, < 2)
+    rouge (1.11.1)
+    safe_yaml (1.0.4)
+    sass (3.5.1)
+      sass-listen (~> 4.0.0)
+    sass-listen (4.0.0)
+      rb-fsevent (~> 0.9, >= 0.9.4)
+      rb-inotify (~> 0.9, >= 0.9.7)
+    sawyer (0.8.1)
+      addressable (>= 2.3.5, < 2.6)
+      faraday (~> 0.8, < 1.0)
+    terminal-table (1.8.0)
+      unicode-display_width (~> 1.1, >= 1.1.1)
+    thread_safe (0.3.6)
+    typhoeus (0.8.0)
+      ethon (>= 0.8.0)
+    tzinfo (1.2.3)
+      thread_safe (~> 0.1)
+    unicode-display_width (1.3.0)
+
+PLATFORMS
+  ruby
+
+DEPENDENCIES
+  github-pages
+  jekyll (= 3.5.2)
+  tzinfo-data
+
+BUNDLED WITH
+   1.15.4