Add support for permanently enabled carrier apps

Read a list of packages from the resources String array called
config_enabledPreinstalledCarrierApps and add these unconditionally to
the list of carrier apps. These packages are carrier apps that will be
enabled, regardless of the SIM card inserted.

Part of CYNGNOS-1650.

Change-Id: Ia8ddb6b022b63ebe8eb555d7c1ea0db4a58821a7