Added resume function that autodetects class and file type.
Updated resume_xyz to resume in nose tests.
Updated create_xyz to create
One more find replace create_repex
bugfux in netcdfio.py
Added docstring to all_subclasses and find_matching_subclass in utils.
Added note to resume docstring discussing how the class lookup works.
Minor cleanup of mcmc / thermodynamics
Merge pull request #61 from choderalab/cleanup_mcmc

Moving volume around.
Merge pull request #56 from choderalab/autoresuem

Added resume function that autodetects class and file type.