Connect, re-connect and read messages from the MNCC socket. Dispatch
the event in case the system got disconnected.
Move the app definition to app.h and use it everywhere. Begin with a
new call for mncc.
* It is written in C and using libosmovty and other data structures
* It is using sofia-sip for the SIP handling as a good library for
such a task
* It is using glib for the sofia-sip event loop integration. In the
future we can write our own root context but right now that looks
like a necessary evil. No glib usage is allowed in this code and
only sofia-glib is linked.