This follows on from #114 and addresses #87, providing an `end`
arg for all these generators, letting you get 'all pages between
Bar and Foo' or whatever it is you may need.

`redefined-builtin` and `too-many-arguments` are small smells,
and fixing them would break backward compat.

Also letting pylint know that we need the imports in __init__.py

* make basic_edit.py and upload.py python-3 compatible

Beaware argument requests from the constructor has been rename reqs

Add 'end' argument to PageList

this is sometimes useful; for instance I have a use case for
getting all pages in a given namespace that are alphabetically
between two specific points (because their names are in a
predictable format that involves alphabetically-sorted dates).
'end' is added as the last kwarg to avoid breaking any current
uses that rely on the kwarg ordering (thanks dan for pointing
that out).

I'll create a CREDITS.md file containing the info removed on this commit and more, so we have a comprehensive history document.

Use 'exec' in py3-compatible manner

[#106] fix GeneratorList with Python 3 (add __next__)

Credit for this fix goes to @tosher:
https://github.com/mwclient/mwclient/issues#issuecomment-154751657
I just figured out exactly what changes his comment suggested,
and poked around a bit to figure out what was going on and why
they're needed.

`GeneratorList` (and things deriving from it, e.g. `Category`)
was broken for iteration purposes in Python 3. In Python 3
the iterator protocol requires a `__next__` method, not a `next`
method as in Python 2. 8d0650cd renamed `List`'s `next` method
to `__next__` and added a small wrapper `next` method to account
for this, but did not make the same change for `GeneratorList`.
So when you iterate over a `GeneratorList` with Python 3, it
winds up calling `List.__next__` (since `GeneratorList` inherits
from `List`), not `GeneratorList.next`. So we don't hit the bit
that turns the results into mwclient page objects, and just get
the raw dicts from the `List` method.

We also have to change a couple of direct calls to `List.next`
to call `List.__next__` instead. If we don't do this, then when
the call originates from a child class, things get messed up,
because `List.next` calls `self.__next__` - and that will wind
up calling the child class' `__next__`, not `List`'s `__next__`.

Confused yet? :)

per https://docs.python.org/2/reference/simple_stmts.html ,
as exec is a function not a statement in py3, the py2 version
has been set to allow the subsequent statement to be a tuple,
so we can invoke it like this to make it both py2 and py3
compatible. Without this, byte-compiling the file fails under
py3.

Fix two typos

- Removing the need to use a double for loop to consume the the result
  by returning a list of revisions rather than a list of pages.
- Parsing the timestamps using the standard parse_timestamp method
- Adding tests

(#84)

Test in Python 3.5 too, now that it is out