The following issues were fixed
* Fixed wrong/missing namespaces
* Fixed obvious typos in documentation
* Documentation not in sync with source code
refs #544
* URLs no longer have to be passed
* watchdog for DB readers to check DB status
In same step:
* fixed some log messages and comments
* allow to self signed SSL certificates
* adjusted namespace for CNetworkUtils (now in network)
* renamed to connectDataReadSignal
* removed unused individual signals, e.g. vatsimMetarsRead -> replace by data read signal + entity flag
* added data in METAR class (kept there, not in airspace monitor) -> reader aware
* the reader will be used in context, but can also be used standalone (ie mapping GUI) GUI
* adjustments in context/airspace as required
** for web reader
** livery
* base class for database based reading (via JSON/web)
* model data reader for models
* 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)
