First working version.
Fixed bug that affected MHD. Orzag-Tang starting to work modulo divB errors.
Changed the stencil. Constraint Transport now works correctly. DivB errors are
at solver error. Orzag-Tang test and magnetized cylindrical tests completed.
Merge branch 'master' of https://github.com/mchandra/grim
Merging github branch and local branch for the first time.