[CrashRecovery] Adding helper methods

Adding helper methods in the platform that would be used from the
module. Currently we would have two helper methods:
1. isModule: this would return whether or not given package is module
2. registerExplicitHealthListener: this would be used to registering
   health listener from Connectivity module.

Test: TH
Bug: 289203818

Change-Id: I74481da973007a60372b3bbecb96919b98751457