Components Can Be Destroyed
closes #4
- Components can now be marked for destruction, and marked components will be removed from the scene at the end of each frame.
- Bullets have a limited life span and destroy themselves after the time limit is reached.
Merge branch 'master' of https://github.com/excaliburHisSheath/Gunship

Conflicts:
	demos/Spectacle/source/Bullet.cpp
	include/Scene.h
	source/Scene.cpp