[mpich-announce] move to GitHub

Hi folks, MPICH has moved to GitHub! http://github.com/pmodels/mpich Come check us out at the new location. We have imported all existing tickets from our old bug tracker as GitHub issues. New bugs (and pull requests) can be submitted directly to GitHub repo. The old MPICH git repositories at git.mpich.org are still available, and will be kept in sync with the official master branch. This may change in the future as we evaluate their utility. Please contact me if you have any questions at this time. Our developer wiki (http://wiki.mpich.org) will be updating over the coming weeks with new information, so feel free to point out any mistakes, omissions, etc. Thanks and enjoy! Ken