Add JSON config utilities for Maps and Play Store

bug: 196497323
Test: locally

Change-Id: I7b31b76ee6047f5659763c4068cedf9b5f2ac9ca
tree: 06c93269c5a0e40f7f447505cd40b7678755fa3b
  1. build/
  2. docs/
  3. emu_test/
  4. libraries/
  5. scripts/
  6. tests/
  7. utils/
  8. PREUPLOAD.cfg