Changed Module::connectTo() to accept also temporary module objects, e.g. as returned by findTag(). As a consequence, the operators [] and () of the modules had to be changed to const.

fixed using out-dated strstream, fixed dump() which was not passing the stream to dump into on to internal calls of VariableNetworkNode::dump()

Made some exception descriptions more elaborate. To achieve this, the dump() functions have been extended to allow writing to an arbitrary ostream.

- allow setting the "eliminateHierarchy" flag in the constructor of a module

This is an interface change which was done in an incompatible way!

added function to flatten teh hierarchy, renamed eliminateHierarchy() into setEliminateHierarchy() for better clarity

added preliminary support for tags to application variables which can be searched for and used to generate virtual modules

fixed duplicated triggers when triggering multiple transfers with the same application variable (e.g. as used in tests frequently)

removed the boost libraries from the test since linking against the boost unit test library leads to crashes on newer gcc/boost versions

fixed sending triggers multiple times when the trigger is distributed to multiple targets (TriggerFanOut takes care of the distribution now)

- delete the copying operator=