Add Carrier Presence to CP2: Phone

Carrier Presence (RCS-based) is required for IMS-based telephony
services: VoLTE, WFC, and VT (Video Telephony). Public API in the
form of Presence column is added to Phone. Initial bit-field is
defined for for VT capability.

Change-Id: Ice78f895acf89a91f7478115e64caeb8d26f5456