Upgrade packaging to 14.5

Add a PEP440Warning to make it easier to silence these warnings

Don't warn on empty non PEP 440 versions

* Normalizes release candidates to 1.0rc1 instead of 1.0c1

Empty versions which are not PEP 440 are more likely to be the
fault of setuptools internals rather than anything a user has done
so these warnings are needless spam in that situation.

This fixes an error where there is a different result for if 2.0.5
is contained within >2.0dev and >2.0.dev even though normalization
rules should have made them equal.

In Python 3.x a subclass will not inherent the __hash__ method from
the parent classes if the subclass defines a __eq__ method. This
means that without defining our own __hash__ the SetuptoolsVersion
classes are unhashable.

* Enables indexing the SetuptoolsVersion objects, triggering the
  legacy behavior warning.
* Enables comparing the SetuptoolsVersion object to a tuple, again
  triggering the legacy behavior warning.

Now that pytest is invoked via setup.py, it should no longer be necessary to continue to support running tests via setup.py test.

Conflicts:
	.hgtags
	CHANGES.txt
	ez_setup.py
	setuptools.egg-info/requires.txt
	setuptools/version.py