Box is available for the calling user.
		
		:param resort.engine.execution.Context context:
		   Current execution context.

def available(self, context):
	
		"""
		Box is available for the calling user.
		
		:param resort.engine.execution.Context context:
		   Current execution context.
		"""
		
		if self.__available is None:
			avail = False
			name = context.resolve(self.__name)
			for box in self.__box_list():
				if box["name"] == name and box["version"] == "0":
					avail = True
					break
			self.__available = avail
		return self.__available