Battle logic connected to endMovementService #142

Ownerships and units are changed according to battle results. This means
that it is now possible to conquer provinces! 

Note that battle tests are woefully inadequate and test what happens
when the attacker wins. Other tests, such as defender win and
BOT-as-defender win are not present. 

Updated server to 0.5.1
Merge branch 'master' of https://github.com/JaanJanno/Georivals.git