GaitSym Code Moved to GitHub

There has been a lot of work done to GaitSym in the past few months (check out some of our recent papers) but no formal releases. To compensate for that all the source code is now on GitHub at which will hopefully mean that people can get hold of the latest version more easily. I've also packaged all the dependencies so that compilation should be more straightforward. It should even work on Linux although there will be some glitches. chimp_cover_image