Command line interface

Added core functionality for controls via command line.
Features so far:
* Simple mapping from string to Action
* Nested control interfaces: Commands can easily be forwarded to inner control structures
* Rough Command line interface that reads commands and forwards them to some inner controller until the user enters "exit"
Working environment

Added some basic files that make it easier to run the application from the command line.
Startup functionality

Started working on actual DC functionality. At this point there is not really something that can be tested. However, there is a dummy connection that simply forwards data through stream objects. I can use this class for testing so that I don't have to set up actual network connections.