Mesh: Hardwire mesh interpolation
BC: Only allow vertices in BC points
Turn off some debugging
Faults: Turn off Line2 test for cohesive fault right now
Merge branch 'knepley/upgrade-petsc-interface' of github.com:geodynamics/pylith into knepley/upgrade-petsc-interface

# By Brad Aagaard
# Via Brad Aagaard
* 'knepley/upgrade-petsc-interface' of github.com:geodynamics/pylith:
  Enable unit tests for refinement with faults (all but hex).
  Update ReverseCuthillMcKee for DMPlex [unit tests not passing].