Fix documentation inconsistency on version specifier

The `,` is the equivalent of an "and".
Also, the pkg_resources section documents and behave like this too:

```
>>> pkg_resources.Requirement('requests>1,>2').specifier.contains('1.2.3')
False
>>> pkg_resources.Requirement('requests>1,>2').specifier.contains('2.3.4')
True
```

docs/setuptools.txt

@@ -571,7 +571,7 @@ project name or version identifier must be replaced with ``-``.
 Version specifiers for a given project are internally sorted into ascending
 version order, and used to establish what ranges of versions are acceptable.
 Adjacent redundant conditions are also consolidated (e.g. ``">1, >2"`` becomes
-``">1"``, and ``"<2,<3"`` becomes ``"<3"``). ``"!="`` versions are excised from
+``">2"``, and ``"<2,<3"`` becomes ``"<2"``). ``"!="`` versions are excised from
 the ranges they fall within.  A project's version is then checked for
 membership in the resulting ranges. (Note that providing conflicting conditions
 for the same version (e.g. "<2,>=2" or "==2,!=2") is meaningless and may