Bump version
Add documentation of differences between pystan and rstan
Fix typos, cleanup
Use 0-indexing in parameter names
Add n_eff and Rhat to summary

Closes #17
Fix minor spacing issue in summary
Fix errant Cython memory allocations
Add tests and improve legibility for ess and splitrhat functions

PyStan ess() returns a slightly different value than RStan's rstan_ess.
I don't know what the source of this numerical difference is. Given the
admonition to take ess values with a grain of salt, I am letting it pass
for now.
Add pandas as a requirement for running tests
No need to install pandas to run tests.
Remove unnecessary Cython import in chains module
Include test data with package
Add reminder about not running python from the source directory
Add log_prob method to StanFit instances

There's a Cython bug that prevents adding grad_log_prob right now.

Closes #8.
Add a module-specific logger
Fix Python 2.7 unicode complaints
v0.2.2 release