Start change to petsc

Link petsc with brew installs.  This only partially works.  Should probably
branch and rebase.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	README.md
Add Hypre formula.  Modify petsc
Change markdown error in README
Change class to PetscFenics

Trying to see if the constant error is due to naming.
Remove dolfin dep on UFC
Comment problem with slepc
Update to fix CGAL 4.3 et al.  Debugging now.
Hacks
Removed formula for deprecated package "ufc".
Update to dolfin-1.4.0.