Add an enum-to-string conversion for QGAUSS_LOBATTO.

Add GAUSS_LOBATTO to MooseEnum in SetupQuadratureAction.

Refs #3906
Refs libMesh/libmesh#350
Adding a simple working/not working test for Gauss-Lobatto quadrature.
Merge pull request #3907 from jwpeterson/gauss_lobatto

Add support for Gauss-Lobatto quadrature in MOOSE