first particle pass

added particle class
added particle system class
there are a limited amount of pre created particles that are either
alive or dead
when a new particle is spawned it its taken form the dead particles and
placed in the active particles
if their are no dead particles to spawn then it can force the oldest
particle to be reborn
added particle shadow rendering

note:
tiles that are on the bottom of the screen due to height are using the
top of the shadow map due to wrapping
this can be solved by extending the texture downwards off the screen but
i dont know how to do that yet