Raises IOError - self_resources.txt not exist
on_load now calls parent's on_load
Raises IOError if its resource file does not exist
Declared and initialized filepath
Read lines from file
Added data format
Deletes data format line
Iterate over each line's content
Responsible for resources for Play class
Removed on_load method
GameState now take cares about loading resources
Defined load_resources
load_resources now responsible for loading resources
Calling member method load_resources from on_load