Merge pull request #3 from tmolitor-stud-tu/master

rtp
Lock free zmq_poll thread
Merge branch 'master' of https://github.com/tklab-tud/umundo
Merge pull request #4 from tmolitor-stud-tu/master

Splitted rtppingpong into two binaries (rtp-sub and rtp-pub)
Merge branch 'master' of https://github.com/tklab-tud/umundo
reindented source again
Make RTP optional and use new ZMQ_SRCFD
Merge remote-tracking branch 'upstream/master'

Conflicts:
	CMakeLists.txt
	apps/tools/umundo-rtp-sub.cpp
	core/src/umundo/connection/rtp/RTPPublisher.cpp
	core/src/umundo/connection/rtp/RTPSubscriber.cpp
	core/src/umundo/connection/rtp/RTPSubscriber.h
	core/src/umundo/connection/zeromq/ZeroMQNode.cpp
Some minor changes