FIX + ENH: Fixed parameter for turning on/off time profiling. Fixed constructors and destructor in connection_m module. Added missing comments into connection_m module.

ENH: Module 'connection_m' was cleaned up, so the dummy Neuron class was moved to the separate module 'neuron_dummy_m'.

ENH: Added Makefiles and Connection module separated into two file - one with module itself and the other one for testing purposes.