README: update to cm-10.2 branch

Change-Id: I340f994886c5e2cf365888103257697aeeaa875f
Signed-off-by: Rohan Mathur <rohanmathur34@gmail.com>
Merge "README: update to cm-10.2 branch" into cm-10.2
Merge branch 'cm-10.2' of https://github.com/CyanogenMod/android into cm-10.2