Merge branch 'master' into jed/ts-eimex

Sync to include Git conversion, PETSC_EXTERN, and minor API changes.

Conflicts:
src/ts/interface/tsregall.c

Commit after merge.

Hg-commit: 529608adef0edbad5c2a5f57f3beefa5703bfae9

moved sf to new vec/is location

Hg-commit: f0665fe4e2bc9d7b33e6af35313fffe9d7c753a8