Adding interface support for remote app (chan_lcr).

Adding interface support for remote app (chan_lcr).

chan_lcr can be handled as an interface. This way it is possible to (e.g.):
- make a SIP phone become an LCR extension with all LCR features.
- make conference calls. (untested)
- perform parallel ringing. (ISDN phone and SIP phones can ring in
  parallel.)
- do voice recoding.

It is still also possible to link chan_lcr directly without interface
(as before).

Documentation/howto for that will follow.