Call libMesh::write_traceout() in mooseError(), mooseAssert()

This is a no-op unless you configure libmesh with --enable-tracefiles.
Without this, you don't get a stack trace from mooseError/Assert() in
parallel.

Refs #4398
Adding a manual call to updateActiveSemiLocalNodeRange() doesn't fix the
issue, the vectors in the DisplacedSystem are not properly ghosted at this time.
Add DisplacedProblem::undisplaceMesh()
Un-displace the displaced mesh before refinement.

Remove attempt at updateMesh() code.
Debugging
Only assign x,y,z values, don't call op= on Nodes.