Updates to makefiles and sources to support third-party builds

These changes remove some unnecessary information from the build files,
such as email addresses of recipients when a build finishes.  Also removes
the RSS plugin dependency since it isn't required for these plugins.  Fix
a cast that raised an error on strict compilation settings. Removed signing
from build.properties.

Change-Id: Id824ccd827ddf6558fe673042207910e0b4e4ca5
8 files changed
tree: 256fbb91d48f328088146fa417711977a2bb7da9
  1. makefile/
  2. src/