update to name hiding checker

[Skip Montanaro]

I modified the name hiding checker I posted this morning to poke around in
classes, functions and code objects' constants looking for more potential
names that hide builtin names.  The new version is available from my Python
Bits page:

    http://www.musi-cal.com/~skip/python/

Skip Montanaro | http://www.mojam.com/
skip at mojam.com | http://www.musi-cal.com/
847-971-7098   | Python: Programming the way Guido indented...