Fixed appearance drawing bugs in gameplay::Stage.
Added code to launch physics.
Fixed a bug when drawing gameplay::Character.
Improved appearance of character.
Fixed a bug when drawing the character in gemapley::Stage.
Added a phdebug option to enable/disable physic debug output.
Fixed a typing error in error msg in graphics::Graphics.
Modified Graphics::setVirtualsize behaviour to apply immediatly.
Fixed a bug in gameplay::Stage::isIn.
Fixed bugs in gameplay::Stage::centerView.