Force use of v2 keys in verifier.cpp

* Will be resolved on merge with upstream TWRP

Change-Id: I6193cc29dc9620db66a3ff69b0a8d1505c913f44
Support verification of ZIPs flashed to secondary ROMs

Change-Id: Icf8856f1b827b6aed8b70c62451d15d2849a5b84
Fix flashing ZIPs to ROMs in image files

Change-Id: I8e56e078ae333f7a8413a724b146b05ca7bcf07f