Transition from QtCore to stdc++ / STL / boost

This looks like a pretty major change, but in reality,
80% of it is just renames of types and corresponding
methods.

The config parsing code has been completely replaced
with a boost::program_options based version. This
means that the config file format slightly changed
(checkout the updated README).

I still expect there to be bugs / unforseen events.
Those should be fixed in follow up commits.

Also, finally reverted back to using pkg-config to
locate and link libruby. Yay for less hacks!

src/sprite.cpp

@@ -37,8 +37,6 @@
 
 #include <sigc++/connection.h>
 
-#include <QDebug>
-
 struct SpritePrivate
 {
 	Bitmap *bitmap;