Removed useless function get_changes. Moved current_diff out of this.settings (and along this.changes)
Handle the case where comparing identical files (e.g. changes.length==0).
ajax.html uses https for jquery so that it can be hosted on a https server.
ajax.html uses full available screen width, auto height is trickier (note that call to _auto_height is commented out in mergely.js).
It's probably no longer simple enough as an example. On the other hand it has a nice drag and drop feature. I couldn't make the "ignorews" checkbos work.
I had to update codemirror.css to have the texteditor height match the container. I tested using Opera browser and there seems to be no autosizing.
