Allowing enable/disable of phone accounts. (2/3)

- Change broadcast listener to listen to PACKAGE_FULLY_REMOVED instead
of PACKAGE_REMOVED.  This ensures re-installing an app will not
remove all PhoneAccounts, losing the enabled states.
- Changed some method names.
- Added PhoneAccountRegistrar methods to enable/disable PhoneAccounts.
- Changed PhoneAccountRegistrar register method to copy over the
previous enabled state for phone accounts.
- Added some TelecomService methods.


Bug: 17306514
Bug: 17408536

Change-Id: Ie8c5e9f3ddec988b42bee682c91671cec904076b