Update 2.10 release notes

- Add information about bug fixes that were recently cherry-picked from
the master branch.

- Move some bug fixes from the new features section to the bug fixes
section.

- Expand the description of the "Add Me" feature on the change screen.

Change-Id: Ie14bab657f5a4f358489b04d16fd330ee66c2c4b
1 file changed