Add an enable/disable phone-account preference.

Preference exists in telecom app and this just adds an intent-preference
to link to it.

This change also shifts the SIP Phone Account ID from the sip Uri,
which can be inconsistent in odd cases, to the profileName, which is
what the SipProfile code itself uses as an ID.

Bug: 20303449
Change-Id: I08ce910c18c94b59a190f49c26c05d5c700e5bf2
9 files changed