Big commit, read description

In this commit the following has been done

- Moved all sockethandling into a base class
- Subclassed sockethandler into BFRCON which will act as a
transportlayer
- BFRCON contains basic rcon commands, prepared to be callable

- cleaned up basehandler
- cleaned up bf4handler

- bf4handler only binds plugins to a specific instance, and creates an
instance of the transportlayer. It also tries to connect to given server
with given credentials

- removed frostbite1 file (it's not needed anymore)
- updated sample_plugin with more information