FIX: Tilde expansion and Github URLs

@drammock The tilde expansion doesn't work in scripts by default, so I changed that to use an environment variable. It would just create a new directory named '~/Builds' at the pwd when the script was run.

For some reason, none of the URLs worked for me. I'm not sure if there is a simple reason or not, but I updated each by copy/pasting them off each repo's clone link.
also this line has a bug: `.../MNE.git` should be `.../mnefun.git`