How to play, better installation, explosion bug

Realised that I did not include instructions of how to play the game. I have therefore added a How To Play screen that can be accessed from the main menu.

Also made an installer for Windows so that you don't have to unpack a zip file.

Finally, I acknowledge a bug in which a bomb explosion blasts through metal blocks to destroy whatever is on the other side. This isn't suppose to be the case. Shall work on fixing that.

In the meantime, enjoy the game!