Allow using template variables in "defaults" field.

Change-Id: I876ab7fa61258e84b00a67325aeb9234aff8fa62
Merge "Allow using template variables in "defaults" field."
Add support for builder Groovy and System Groovy

Closes-Bug: #1251869
Change-Id: Ibc49e1aca7b33eb9c0c21472a924cb375069ee51