Merge branch 'master' into jgrpp

# Conflicts:
#	src/blitter/32bpp_anim.hpp
#	src/blitter/32bpp_base.hpp
#	src/blitter/8bpp_base.hpp
#	src/blitter/null.hpp
#	src/cheat_gui.cpp
#	src/gfx.cpp
#	src/linkgraph/linkgraph.cpp
#	src/spriteloader/grf.cpp
#	src/station_cmd.cpp

src/blitter/base.hpp

@@ -224,7 +224,7 @@ public:
 	 * @param height The height of the buffer-to-be.
 	 * @return The size needed for the buffer.
 	 */
-	virtual int BufferSize(int width, int height) = 0;
+	virtual size_t BufferSize(uint width, uint height) = 0;
 
 	/**
 	 * Called when the 8bpp palette is changed; you should redraw all pixels on the screen that