Pixel array

Moves SFML depedent code out of DCPU-16 devices.
Does a more sane keyboard events handling and avoid changing windows focus to use debug mode short-cuts.
Implements splash screen of monitors and tricky PowerON fade in effect.
CGM mode 4 fixed.

**TODO**: SFML monitors need work. Perhaps make a abstract class (the objective its move out all SFML dependency from DCPU-16 & devices code), that they inherit and monitor devices, can use these abstract class, to handle better splash, power on and other related stuff. Actually does the work, but not ends to work when the VM is reset. Also, is necessary make a 8x8 font (I have in bitmap). Perhaps a small tool that reads PBM and generates  8x8 and 4x8 fonts could be very useful.