Re-factored SolutionUserObject to correct variable numerbing mismatching problem with MeshFunction
(closes #3517)
Restored old syntax that requires variables names to be listed
https://github.com/libMesh/libmesh/pull/307
(refs #3517)
Restored old syntax to input files (refs #3517)
Merge pull request #3664 from aeslaughter/soln-uo-dual-params-3517

Repiairs SolutionUserObject w/o relying on another libMesh update
Merge commit '61684767435e0cd8cdf9bedd46a630557cf0b09c'