Added euqals and hashcode to Coordinates
Added equals and hashcode to ImmutableNode
Implemented todos in ImmutableBoard (except toString)
Updated immutableBoard's old tests to reflect new implementation
Immutable node is now final
Fixed and added new test case for ImmutableBoard
fixed documentation and format, removed old unused methods
Added documentation about friendlies
Changed to use friendlie ImmutableNode
Added back get playerIDs method
Changed functionality of isGameOver to function with more than two players
Renamned SimpleRules to Rules and also its unit test
Cleaned up model and added unit tests for the model to the unit package
Updated name for SimpleRules in dependencies
Fixed comments after review
Merge pull request #42 from ragnhildkarlsson/Model-cleaning

Model cleaning