Continued working (several changes)

Changed resolution to 800x600
Changed application title
Removed World.mSpawnPosition
World.mSceneLayers is now private

Update World::Layers (LAYER_COUNT, LAYER_MAP, LAYER_GENERAL,
LAYER_FOREGROUND, LAYER_HUD)

Lua: Bound sf::FloatRect (in Lua it's called FloatRect without sf)
Lua: Removed Entity.Test
Lua: Added LAYER_ enum (see World::Layers)
Lua: Added Entity.Activate( LAYER_ enum )
Lua: Added world.GetBounds
Lua: Added world.SetBounds (FloatRect)
Lua: Updated world.GetSceneLayer (probabbly still broken; untested)