Moving the lid-driven cavity test from the combined module to Navier-Stokes.

Closes #3036.
Removing dummy 'simple diffusion' test from Navier-Stokes module.

Refs #3036.
Removing MooseVariableBase::index() (closes #3094)

It is not needed, since it returns the variable number which is the
task done by number().
Merge pull request #3097 from jwpeterson/move_ins

Move the Navier-Stokes test out of combined
Merge commit '1a728cb9c302638479c2489d832144ca6dff69fd'
Removing mesh dimension restriction from PenetrationLocator (closes #3099)

When having a higher dimensional mesh and using lower-dimensional
elements, PenetrationLocator cannot deal with it, since it assumes that
all elements have dimension equal to the mesh dimension.
Used new default coupling in GBEvolution.C
Used new default coupling in GBEvolution.C #3093
Merge pull request #3098 from andrsd/3094

Removing MooseVariableBase::index() (closes #3094)
Merge commit '3410e091c6ce9a7bc5e42fcab649d68355ed8d1f'
Limit around_normals test to serial mesh (#3078)
Fixing a slight namespace issue after a namespace issue was fixed in libmesh.

Refs #000.
Merge pull request #3103 from tonkmr/feature_3093

Feature
Merge pull request #3104 from aeslaughter/sidesets-parmesh

Limit around_normals test to serial mesh
Merge commit '9cc3b76f325c1a376e550655b474ee422ced47e7'
Merge commit '0dd822b115b41e518733b3cfbb6bcb31cfb3c5fc'
Merge pull request #3100 from andrsd/3099

Removing mesh dimension restriction from PenetrationLocator (closes #309...
Merge pull request #3106 from jwpeterson/fix_namespace

Fixing a slight namespace issue after a namespace issue was fixed in lib...
Merge commit '6d46449850827aea56493a71d196676964a3f45a'
Merge commit '25aabd3eb7775e937fb208472d161ddbbc775afe'