Fingerprint: Make the existing FingerprintService semi-useful.

- Add explicit actions for authentication so HW has
  a chance to power down when not in use.  The other
  option would be to start scanning when startListening
  is called, but that would force apps trying to enroll
  to start trying to authenticate immediately before they
  start enrollment.  That didn't seem like a good idea.
- Update to CM Fingerprint HAL 1-1.
- Extreme care needs to be taken to use this
  API.  It's not exactly robust against multiple
  clients stepping on each other.
- All of this goes away in M.

Change-Id: I6e34935cdec5e8eeabeac6f8cf9fb58e689cb889