Bug 988571 - Part 0: Fix Sync 1.1 upgrade receiver intent filter.

Per [1], as discussed at [2], MY_PACKAGE_REPLACED is only available in
API level 12 and later.  The following appears to work more generally;
there is some confusion as to exactly whether android:scheme="package"
restricts to just the current package, but it certainly does locally.

[1] http://developer.android.com/reference/android/content/Intent.html#ACTION_MY_PACKAGE_REPLACED
[2] http://stackoverflow.com/a/2134008
Bug 988571 - Part 1: Add FxAccountUpgradeReceiver boiler-plate.
Bug 988571 - Part 2: Unpickle any pickled accounts on upgrade.
Bug 988571 - Part 3: Move accounts from the Doghouse to Separated on upgrade.
Bug 988571 - Part 4: When upgrade is required in UpdateCredentials, transition to Doghouse.

We always route through Separated so that the user has a chance to enter
fresh credentials and recover their Account.
Bug 988571 - Migrate Android Firefox Accounts from Doghouse to Separated state on application upgrade. r=rnewman