The maintainers of pyOpenSSL have deprecated the tsafe module
because it is neither used nor complete. It was removed from
in paste in 78dd2ec01384 but because of a lack of test coverage
it caused a regression as described in #19.

Reviewing the code and pyOpenSSL, it appears that the right
fix is to simply not subclass the SSL.Connection, and let
get and set timeout be called on the socket object that
Connection keeps, without a lock.

A concern here is that if someone is doing something multi-
threaded with paste/httpserver the removal of the use of tsafe
may present some issues. On the other hand, if someone is
doing something multi-threaded, one hopes they are using a
more robust web and modern web server.

Fixes #19

* Quiet OpenSSL deprecation warning

It would fail if the length of bytes and unicode differs.

It now passes non-bytes to `Form` directly.

* py3 fixes for form handling in paste.fixture

It uses "not six.PY2" in contrast to other places in the code to be
forward-compatible.

I've not looked too closely, but it might make sense to decode body/text
in the beginning already, instead of having it as bytes internally?!

Also, like mentioned in [1] already, it should probably use the correct
source encoding?!

1: https://github.com/cdent/paste/blob/36e5b8bd16a6063ec654faf04541f3a20d19f7fe/paste/fixture.py#L820

* Add test, using/fixing SlowConsumer form app