What is new in SEMS version 0.10.0

Between 0.9.0 (CVS) versions and 0.10.0, quite a lot has changed.
Almost 50% of the code has been rewritten: the design has been
simplified a lot, and to make a slim, clean core a lot of 
functionality has been dropped. Instead, for the core we just
focus on the essentials: basic signalling, session and media 
handling, and loading plugins.

An inter-plugin API ("DI-API") has been introduced, such that 
functionality can be added using plugins, everybody can implement
their favorite functionality as a reusable plug-in, and applications
can be built in a modular manner.

A new kind of modules, session component plugins, can even modify the 
basic signaling behaviour, the session timer plugin is the first one to
use this. 

Major additional changes:
 * Interface to Ser has been rewritten.

 * Application plug-in interface has been partially rewritten. 
   Applications are now exclusively event driven and asynchronous.
 
 * Media is processed by one thread for all sessions, improving
   the performance extremely due to less task-switching

 * Back-to-back User Agent (B2BUA) functionality has been added.

 * IVR python code has been completely rewritten: Applications are
   now developed in the IVR like their C++ counterparts

 * Session-Timer has been added (as module), replacing the ICMP 
   watcher

 * Adaptive playout buffer has been added

 * Audio processing simplified