Python guidelines cleanup

[Jason L Tibbitts III]

Also, When using the python_provide macro as detailed in the guidelines,
I can't seem to get fedpkg to generate an srpm:

> fedpkg srpm
error: line 36: Unknown tag: ERROR: not recognized.
error: query of specfile /home/tibbs/work/fpkg/python-requests/python-requests.spec failed, can't parse

That line is just:
%{python_provide:%python_provide python2-%{srcname}}

Of course if I use %if %defined python_provide everything's OK, but
that's three lines instead of one.

I know tomspur tested this so I must be missing something else.  I just
can't figure out what it might be.

 - J<