added functions to network module to retrieve acquisition/recording status and the current recording path

Fixed bug in NetworkEvents::createZmqContext.  Added Python example script for sending network events.

Included unistd.h for successful Linux compile, known fix from https://github.com/open-ephys/GUI/pull/150

0MQ is included, but not linked (unless you define it in
NetworkEvents.h).
Redrawing events are not called for some reason.

Fixed a bug in conditional operators to compile eCube support
Added exception handling code to allow for errors during source creation