Adding CompositeFEMFunction

This and CompositeFunction should be moved to libMesh after a little
testing of the former.
Support ParsedFEMFunction Dirichlet BCs
Handle PARSED_FEM_DIRICHLET case
add dirichlet_fem regression test

At least this is enough to prove that the FEMFunctionBase
DirichletBoundary code works as a plug in for the FunctionBase
DirichletBoundary code.
Delay construction of ParsedFEMFunction

If we just store the strings to be parsed, we don't need a System
argument until we have one in hand.
Use the correct dirichlet_fem input/data files
Try to reinitialize FEMFunction Dirichlet BCs

This isn't giving correct results yet, but (with the proper libMesh
branch) it's at least no longer crashing.
Need EquationSystems to reinit constraints

This whole section of code is hideous and needs libMesh-based
refactoring, but at least it works now.
parsed_fem_dirichlet boundaries now work

So let's get the regression test set down.

This is a horribly understabilized case, but that should be fine for a
regression test.  I don't want to use a finer mesh because I'm afraid
that the Dirichlet<->Neumann transition might be borderline somewhere
and rounding error flipping the sign of u=+/-epsilon might then
trigger a larger change.
Bugfix for locally_h_refine in parallel
More verbosity from locally_h_refine
Bugfix for default zero VelocityPenalty values
Fix unused variable warning
Moving post-input-refinement to a stand alone function.
Add accessor for MeshBuilder from SimulationBuilder

This is needed for doing post-input refinement when there's
a restart file. We should really refactor SimulationBuilder to
just have accessors for each of the builder modules. I still like
containing everything in SimulationBuilder to keep the Simulation
API simple, but redoing function calls is stupid and everything
in the builder modules should be const anyway.
Make do_mesh_refinement_from_input const
Rename read restart function to something more descriptive
Decide when to do post-input refinement

Based on presence of restart file.
Need to reinit after the mesh refinement
Warning+temporary fix for locally_h_refine+restart