add read_history to munge; moved trajectory_plotter to model_plotter;
add "option parser" to model_plotter, to build grid, select, and mask;
decouple 'grid' from parse_axes; add ability to apply 'mask' to > 2D models


git-svn-id: svn+ssh://svn.mystic.cacr.caltech.edu/mystic/mystic@742 968178ea-60bd-409e-af13-df8a517b6005
Merge branch 'master' of https://github.com/uqfoundation/mystic