Move remaining custom deleter functions to their respective owners

	Canvas_FreeSurface to SDL_Canvas, Display_FreeSurface to SDL_Display
and TTF_FreeSurface to SDL_Font.
Clean up namespace wrapping
Fix YAML parsing err
Add two additional mouse buttons (6..7)
Mark off TODO items as completed
Add 8-bit, 15/16-bit & 24-bit pixel blitting & reading support

	We also correct a small bug in the calculation of 32-bit pixels; we
were using surface width instead of surface pitch.
Add gcc to the build matrix
Add separate make, make install & uninstall steps
Fix make install, uninstall steps
Make (SDL) Image, Cursor, MessageBox, App, Timer virtual destructors

	We wish to express that it is OK to inherit from these classes.
Make onInit, onExit optional interfacing
Ignore *.tags files (ctags)
(Greatly!) clean up installation script for header files
Add support for distributing with user's frameworks / OSX App Bundle
Add master branch to the whitelist