ENH/TST: Add chi square distance coefficient, and tests.
TST: Add another test for values, this time from an example in L&L.
TST: Now that we have chi square, make sure scalings in CA work right.
TST: Trivial test for input type.

I'd like to accept numpy array-like stuff too, though
DOC: expanding CA docstrings.
DOC: and RDA docstrings
DOC: A few updates to CCA docstrings.
DOC: typo.
DOC: another typo.
Merge pull request #102 from Jorge-C/more_ordination

More ordination