Wiki v2

I have started moving some bits of the old wiki to the new wiki, there is quite a lot of content, so if anyone wants to help :) I'm also thinking the Yhc website should just be the wiki, no static pages at all - so all the static content probably needs moving as well.

Hopefully once all this is done we'll have the best documented compiler.

Update: all done, there should be nothing on the old wiki which isn't on the new one - I also reorganised quite a bit at the same time.