Loacking sdl surface.

According to sdl documentaion surface should be locked when reading or
writing to surface->pixels. However, no problems has yet arrised when
using Class Texture. But in order to be on the safe side changes was
made.
Removed unneeded private member variable.
Importand bug fix, init sdl and ttf is fixed.

Classes that inherites from initttf and initsdl do this in order to fix
the initialization and clean up of sdl and sdl_ttf correctly.  But
copying or assignment operator was not considered but that is fixed now.
Unneded initialization of local member variable.

Increased code readability.
Added color class to project settings.