Refactored tests
Tiny change to docstring
Merge pull request #101 from choderalab/refactor_tests

Refactored tests, added test for computeGeneralExpectation bug
Merge pull request #100 from mrshirts/nk

Fixes for general expectation computation.
Added new solver code
Initial checkin of SGD like code
Updated to use random subsets.
Temp checkin sgd
Minor fixes
Fixed brokenness after adding s_n
Deleted extra file
Reverted some preliminary changes.
Fixed spacing issue.
Added KAB covariance estimator
Adjust rcond in np.linalg.pinv()
Added svd-ew-kab method for covariance calculation.
Minor updates to benchmarking scripts
Don't allocated N^2 storage in covariance method inverse.  See #106
Add check for only one state with samples before running solver.
Added extra tests for two state checks.