Merge pull request #3 from esheldon/master

upstream sync
prep to use as base class
added code to collate an arbitrary set of files
added docs
added check for non-finite step sizes
did merge. whew.
Merge pull request #5 from esheldon/master

fixed bug in get_chunks
bug fix from merge
Update mcmctester.py
added new function
Merge branch 'master' of https://github.com/beckermr/gmix_meds
fixed a bug when switch to new config files was made
changes to enable processing of files
fixed temp dir processing
only do nbrs if needed
Merge pull request #16 from beckermr/master

merge for non-finite matrices; new functions to collate files