Add updated URLs
remove link to blog
Merge branch 'playwithyourmusic.org' of github.com:p2pu/mechanical-mooc into playwithyourmusic.org
Merge branch 'playwithyourmusic.org' of github.com:p2pu/mechanical-mooc into playwithyourmusic.org
Merge branch 'playwithyourmusic.org' of github.com:p2pu/mechanical-mooc into playwithyourmusic.org