moved all dynamic loading into xml_file_loader. Added a method for listing installed/discoverable dynamic modules to env class.
added rng schema methods to test models and removed rng files from them. removed rng installation from cmake module macro.
added master and module schema dumping to cyclus binary. added schema model test (that schema parses).
moved heavy stuff out of xml-file-loader constructor. renamed LoadAll to LoadSim.
Merge pull request #608 from rwcarlsen/schema

Changes module schemas to be returned by a model class method.