Structure changes for SPoint, now MPoint for mutable point
MissileThrower for vessel
Asset generation post-build script
	modified:   assettools/AssetGenerator.cpp
	new file:   build_assets.py
	modified:   stigame/GuiState.cpp
	modified:   stigame/ISprite.cpp
	modified:   stigame/ISprite.h
	new file:   stigame/MPoint.cpp
	new file:   stigame/MPoint.h
	modified:   stigame/SPhysic.cpp
	modified:   stigame/SPhysic.h
	modified:   stigame/SPoint.cpp
	modified:   stigame/SPoint.h
	modified:   stigame/SRect.h
	modified:   stigame/StiGame.cbp
	modified:   stigame/Viewport.cpp
	modified:   stigame/Viewport.h
	modified:   stigame/ViewportArea.cpp
	modified:   stigame/ViewportArea.h
	modified:   stiuniverse/AssetGenerator.cpp
	modified:   stiuniverse/AssetGenerator.h
	modified:   stiuniverse/MainState.cpp
	modified:   stiuniverse/MainState.h
	new file:   stiuniverse/MissileThrower.cpp
	new file:   stiuniverse/MissileThrower.h
	modified:   stiuniverse/SpaceVessel.cpp
	modified:   stiuniverse/SpaceVessel.h
	modified:   stiuniverse/StiUniverse.cbp
	modified:   stiuniverse/main.cpp