android: removed network.ClientManager
android: added controller.ClientManager and moved some responsibilities to from the StartActivity to the ClientManager
android: added basic SelectCarActivity as ListActivity
android: added async network tasks
playerclient: got rid of 'Car'. was replaced by the car id.
The 'Car' used some Java SE stuff (e.g. awt) which is not available on Android.
android: implemented Connect to host.
Merge branch 'master' into anroid/feature/join-a-game