Merge pull request #4265 from RosettaCommons/vmullig/clean_up_parameters_hh
Clean up Parameters.hh and Parameter.hh a bit to reduce transclusions.
This is part of Andrew Leaver-Fay's attempt to improve compilation efficiency by reducing unnecessary inclusions. Some of my parametric code puts too much in header files, necessitating inclusion of headers like Residue.hh (which themselves include a lot of other stuff). I can clean this up.