added server project files
progress on xmlrpc-communication

added queries to:
- check server connection
- register user at server
- retrieve id of username
- create game at server
progress of last weekend
added message processing up to choosing and sending black card alternatives to user
extracted gamerule handling of server application in designated abstract class structure
streamlined notifications
added handling of dealt white cards
added xmlrpc-config for local, server-related configuration
added asynchronous server queries at main-activity
added server communication up to choosing of a winning card
mergehead