Added still more imprecision to this test since it was actually failing on Python 2.6
After getting some experience going through the docs and using this feature, renamed FLOAT_COMPARISON to just FLOAT_CMP for the terseness.
The regexp that searches for floating point numbers has a list of characters that may indicate the 'beginning' of a float.  I think this is a bit arbitrary in fragile, as evidenced by the fact that I had to add a left-parens to the list, as it can certainly precede a float.  Might change this later, but it's okay for now I guess.
Converted several doctests to use FLOAT_CMP