Several changes:

1) Moved all retlocs code to retlocs.py to speed execution.
2) Modified doc-shortcut to use envars and added ability for te to open
   to line number
3) Added ln2scr that symbolically links files to a mirrored directory in
   the users scratch directory.  This is useful for linking input files
   for a finite element analysis to a scratch directory where the analysis
   can be run.