Help wanted: Documentation review

[liebharc]

I tried my best to provide a complete and helpful documentation (http://liebharc.github.io/basic_dsp/basic_dsp/). But it for sure has lots of room for improvement so I really would appreciate if someone could review it. I would expect parts of it to be confusing, wrong and/or incomplete. Also I'm not a native speaker so spelling and grammar must be odd too.