Merge pull request #1 from lukeolson/master

Update petsc to include downloads.  Change dolfin.rb to use pip for some python

Tried and tests.  Still some issues.
Update README.md
Update README.md
Rename local PETSc formula.
UFC is now deprecated.

The code for UFC is now contained in FFC. The formula for UFC should be
removed once the new FFC is released.
Merge remote-tracking branch 'upstream/master'

Conflicts:
	README.md