Freshening Up The Tutorials Again

I've just been through the second tutorial that deals with creating a tile based game, getting tiles to the screen, making grass and stone tiles from textures and that sort of thing. Once again a few mistakes have been fixed and complicated sentences have been broken down into simpler ones. I also have added source code. It should be much better to follow now. (I've also removing comments dealing with the older version so they wouldn't be confusing! They're only hidden not deleted :D All the issues they addressed have hopefully been resolved.)

I also spent a little time with the first tutorial again improving the formatting and add two more source code snippets. I will undoubtly in the fullness of time work my way through the rest of them.