Make SiteCOllection.is_valid cast to regular bool.
Revert "copied from rubicon, test pycharm"

This reverts commit 6575cd3d506d7952a9b2872c10045c52be6dfbed.
Improve core docs.
More doc improvements.
PMGJSONEncoder now intelligently converts numpy types.
Use monty's json.loadf.
Cleanup fab deployment file.
More cleanup.
Switch to new monty.tempfile.ScratchDir.
Update required monty version.
Merge branch 'master' of github.com:materialsproject/pymatgen
Change badercaller to use monty.tempfile.
Minor cleanp.
added test file