imp is deprecated and will go away in Python 3.12 (which is very
soon). The preferred replacement is importlib.

However, importlib is not available in Python 2.7, so we want
to keep both in order to maintain 2.7 some semblance of 2.7
support.

This implementation is based on the importlib docs [1] and passes
the quite robust tests that are already present for the urlparser
module. Unfortunately there's no good way to be 100% certain that
this works for all the many ways that Paste can do an import. So
this patch is mostly hoping that test coverage is sufficient.

[1] https://docs.python.org/3/library/importlib.html#importing-a-source-file-directly

Fixes #75

A Python 3 application might only define `__next__`, not `next`.  Use
`six.next` instead.

This is very similar to https://github.com/cdent/paste/pull/53, and was
apparently missed there.

* Update next() to work with py3

* wsgi.errors is supposed to be text, fixes ErrorMiddleware on py3

The BaseCookie import is cleaned up to use six.

Where splittype and splithost are used the returned values are not, so they can go away.

* Patching auth ticket to be python3 compatible

In py2 an array is created and sorted, and in py3 an array of the items needs to be realized in the same fashion hence the sorted(•) fix. Otherwise the code will fail on Python 3 since dict.items() returns a view on the items which doesn't have a .sort() method.

If the app-iterator being passed in is not defining `next()` (e.g. running under py3 and only defined `__next__`), this will currently crash.

Fix by using `six.next` which will use `__next__` or `next` as appropriate.

* add ipv6 support by setting address family