Refactoring is done*.

The refactoring is finished, the code is consideraby better orginized
and somewhat better looking. However due to some very strange linker
errors, I can not split the particle or particlecontroller classes into
mutliple files. I will now branch the 3d version.

I might (read: will when i feel like it) come back to this version once
in a while as I learn new stuff and imrpove it.