Fix build on GHC 7.8.3
Bump genifunctor version
Try to get travis to install cvc4 [5]
Support cvc4
Enable the test suite again
Use new unification-fd
Update README
Merge branch 'master' into fpi

+more stabs at fpi

Conflicts:
	hipspec.cabal
	src/HipSpec/ATP/Provers.hs
	src/HipSpec/Id.hs
	src/HipSpec/MakeInvocations.hs
	src/HipSpec/Params.hs
	src/HipSpec/Property.hs
	src/HipSpec/Read.hs