- Prevents a NullPointerException in ice4j's Connector#stop() which appears quite often with unknown side effects.
- Prevents a NullPointerException in ToolsMenu related to the Jitsi VideoBridge menu item which causes of long chain of other exceptions and, eventually, prevents the application from completing its startup.
- Moves the C source code of JNI PortAudio library from Jitsi/net.java.sip.communicator to libjitsi/org.jitsi. Removes a couple of Java method and C function implementations each of which repeats three times. Fixes possible cases of leaving native callback threads which have been attached to the JVM in undetermined states.

Commits an initial version of the libjitsi library which should be fully functional with respect to neomedia/MediaService and should be usable with and without OSGi.