feat($timeout): allow invokeApply to be a scope on which $apply will be called

This is useful when combined with partialDigest.
Before this, $timeout was only able to call $apply on the $rootScope.
feat($interval): allow invokeApply to be a scope on which $apply will be called

This is useful when combined with partialDigest.
Before this, $interval was only able to call $apply on the $rootScope.