Made the Keyfile in the client optional

Using this client to test servers from the students I found that it is mandatoryto provide a keyfile, as I was too lazy to generate one I simply made the keyfile optional. When a player_* name is provided an Error is thrown when no keyfile is found
Little clean-up for windwarriors pull request
Merge branch 'pr/2'
Pull request from https://github.com/windwarrior/rolit/commit/0ee8779e35fb8f4178e21785e253509e30f05351