CleanSpec for 4.7
Various commits for 4.7:
- make gcc 4.6 default
- add optimization parameter to lunch
Change Email2 reference back to Email

Change-Id: Id07d81793d2921be95b30f608cc558312f210c4e
Signed-off-by: Roger Chen <cxr514033970@gmail.com>
Don't build calendar
Custom Purity ota_from_target_files