Prepare for release v1.4.0-rc2

Update version stamps as well as the release notes.

Signed-off-by: David Brown <david.brown@linaro.org>
diff --git a/README.md b/README.md
index fb7e9fa..9488506 100644
--- a/README.md
+++ b/README.md
@@ -6,7 +6,7 @@
 [coverity]: https://scan.coverity.com/projects/mcuboot
 [travis]: https://travis-ci.org/JuulLabs-OSS/mcuboot
 
-This is mcuboot, version 1.4.0-rc1
+This is mcuboot, version 1.4.0-rc2
 
 MCUboot is a secure bootloader for 32-bit MCUs.   The goal of MCUboot is to
 define a common infrastructure for the bootloader, system flash layout on
diff --git a/docs/release-notes.md b/docs/release-notes.md
index c42e7bc..1d0f842 100644
--- a/docs/release-notes.md
+++ b/docs/release-notes.md
@@ -17,11 +17,20 @@
 
 ### About this release
 
-- Fixed CVE-2019-5477.  This fixes an issue with a dependency used in
-  the generation of the documentation on github.
+- Fixed CVE-2019-5477, and CVE-2019-16892.  These fix issue with
+  dependencies used in the generation of the documentation on github.
 - Numerous code cleanups and refactorings
 - Documentation updates for multi-image features
 - Update imgtool.py to support the new features
+- Updated the mbed TLS submodule to current stable version 2.16.3
+- Moved the mbed TLS submodule from within sim/mcuboot-sys to ext.
+  This will make it easier for other board supports to use this code.
+- Added some additional overflow and bound checks to data in the image
+  header, and TLV data.
+- Add a `-x` (or `--hex_addr`) flag to imgtool to set the base address
+  written to a hex-format image.  This allows the image to be flashed
+  at an offset, without having to use additional tools to modify the
+  image.
 
 ## Version 1.3.1
 
diff --git a/repository.yml b/repository.yml
index 93e5c25..0cd408d 100644
--- a/repository.yml
+++ b/repository.yml
@@ -26,7 +26,7 @@
     "1.2.0": "v1.2.0"
     "1.3.0": "v1.3.0"
     "1.3.1": "v1.3.1"
-    "1.4.0": "v1.4.0-rc1"
+    "1.4.0": "v1.4.0-rc2"
 
     "0-dev": "0.0.0"        # master
     "0-latest": "1.3.1"     # latest stable release
diff --git a/scripts/imgtool/__init__.py b/scripts/imgtool/__init__.py
index 8f6e848..804f0d6 100644
--- a/scripts/imgtool/__init__.py
+++ b/scripts/imgtool/__init__.py
@@ -12,4 +12,4 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-imgtool_version = "1.4.0a3"
+imgtool_version = "1.4.0rc2"