Dev

* fixed null reference bug when audio parts transition to orbit (packed) rather than destroyed.
* stripped line endings, see https://help.github.com/articles/dealing-with-line-endings
* added .gitattributes file with LF line endings config.
* added nifty javascript tool for simulating/visulizing mach angles.  See /docs
* added diagram of Soundscape hierarchy.  See /docs
* removed hypersonic Soundscape (state).  More on that in forum thread.
* cleared up variable names for shockwave and dynamic effect calculations.  (Reminder to self, don't reorganize anything when tired.)