* some improved comments and information
* QMetaObject::invokeMethod in tool.cpp as thread safe invocation
* common base class for threaded readers
* removed event class, using QMetaObject::invoke instead for forcing calls in main event loop
* stop methods for readers, as used for graceful shutdown (preparing for thread safe destruction of objects)
* graceful shutdown for network context
* calls in tool now via inkoke for thread safety (only thread safe methods called directly)
* changed .pro / .pri as required
* Used info from project class in network_vatlib
* Checks / info in GUI/core (e.g. console)
* const * versions of systemNameAndVersion / simulators, as mentioned in https://dev.vatsim-germany.org/issues/217#note-4
