Update IntentFactory to construct intents using RemoteActionTemplate...

objects that are returned by the model

1. TemplateIntentFactory is the intent generator. It reads from the
   templates that are returned from the model, and construct the
   intents accordingly. If template is missing, we fallback to use
   LegacyIntentFactory.
2. LegacyIntentFactory is the old(existing) intent generator.
3. Added a flag to allow us to switch between them.

Test: atest TemplateIntentFactoryTest.java
Test: atest LegacyIntentFactoryTest.java

Change-Id: I7bdcc73321f5a0160c5ff0edf1a2095119f4dcb1