- Rect no longer inherits from SDL_Rect
- renamed vcmi functions that used SDL naming format
- moved all functions in SDL_Extensions file into CSDL_Ext namespace
- SDL_Rect is now used only by SDL_Extensions, all other code uses Rect
* Changed most gui classes to use shared pointers
* Store and use IImage as shared_ptr
* CSpellWindow redesign
* AdventureMapClasses cleanup
* CLabel: store background as smart pointer
* Store CObjectList items as smart pointers
* Removed destroy function of list item
* Store toggle buttons as smart pointers
* Use CComponent as smart pointer
* Attempt to fix artifact merchant drawing
