Gird for Battle should work if targeting only one creature

[antonioalonzi]

TODOS:

• Extend PutPlusOneCountersOnCreaturesTest adding an extra Gird for Battle to player hand.
• At the end of the test add extra code to play it by targeting one only creature and click continue
• Assert that spell is triggered and counter is added (test will fail as this functionality is not available)
• ClientEventsReducer.CONTINUE_CLICK verify it enters into the if TurnUtils.getCardIdSelectedToBePlayed(newState) (make sure that the creature is cast).
• the logic should be, only target with optional false should be mandatory. Targets with optional true can be omitted
• CastService.cast() should be called on the backend and put the counter correctly (it already updates the UI with any changes to the GameStatus). I expect no changes in there.

I'm sure some changes are required, although cannot add any more info to this ticket without picking it up myself.