Fixes to pass release tests.  cytoolz now matches toolz.

The release tests (which are run when "dev" is not in the version) made matching `toolz` rather painless.  They identified several small things that are easy to overlook (and, indeed, *were* overlooked).

I should also note the "test_none_safe.py" tests have proven to be occasionally useful.  For instance, this is how I learned that even inline functions need to return `object` in order for exceptions to be raised.