Remove incubator references from mynewt dev email

Also use a single email for all packages.

Signed-off-by: Fabio Utzig <utzig@apache.org>
diff --git a/boot/mynewt/pkg.yml b/boot/mynewt/pkg.yml
index c1c0cc7..0c55674 100644
--- a/boot/mynewt/pkg.yml
+++ b/boot/mynewt/pkg.yml
@@ -20,7 +20,7 @@
 pkg.name: boot/mynewt
 pkg.type: app
 pkg.description: "Mynewt port of mcuboot"
-pkg.author: "Fabio Utzig <utzig@apache.org>"
+pkg.author: "Apache Mynewt <dev@mynewt.apache.org>"
 pkg.homepage: "http://mynewt.apache.org/"
 pkg.keywords:
     - loader