Telephony: Samsung STK Support
Squashed Commits of the following:
    Add Samsung STK support (telephony part)
    Support for SMS-based SIM applications.
    Partially rewritten the original patch by Jüri Schultz to be less intrusive.
    Change-Id: I15d2de1781a2823e24941dd792db3d372578aa9f
    Samsung STK: Add USSD support
    Allow USSD-based STK applications to work
    Change-Id: I483f37a44a6c3ed43eefcf979e17b84877d03f93
    Samsung STK: Fix SMS-based STK
    SEND_SMS was falling through to SEND_USSD (which used to do nothing
    until USSD support was added) causing an Exception because cmdParams
    is not an instance of SendUSSDParams.
    Fix by using type-checking instead of checking if Samsung STK is
    enabled (because SendSMSParams and SendUSSDParams will only be
    created if Samsung STK is enabled.)