If the delta time dt passed to cocos2d::Timer::update(float) is longer than the
interval of the timer, then the timer will be triggered several times even if
the selector is unscheduled during the call.
This commit adds a flag in cocos2d::Timer stop the update loop if the selector
has been unscheduled.
* Fixing issue where Scheduler::unscheduleAll() would not unschedule functions scheduled with Scheduler::performFunctionInCocosThread.
* Removing clear of _functionsToPerform from unscheduleAll, based on code review feedback. Adding a function removeAllFunctionsToBePerfomedInCocosThread, which will remove all pending functions scheduled with performFunctionOnCocosThread.
* Adding test case for Scheduler::removeAllFunctionsToBePerformedInCocosThread
* Adding proper cleanup code to Scheduler test for SchedulerRemoveAllFunctionsToBePerformedInCocosThread
j-jorge