use a prop to set the Gummy release version for global access

Change-Id: I4e1ddbeaff43fd64c021b7972b5f00be4362770c
bump version to M2.1

Change-Id: I06386b2fb2a60fee071c7cb7df3979ec0b2d447b
Merge remote-tracking branch 'tg/kk4.4' into kk4.4