[Shtoom] Shtoom licensing.

[Anthony Baxter]

I've had a couple of people query as to how the LGPL should
apply to Python code such as shtoom. The following document
attempts to clarify this. I'm open to ideas about possibly
dual-licensing shtoom, so long as the basic goal of the license
is maintained.

The Shtoom License
------------------

Shtoom is licensed under the GNU Lesser/Library General Public License
(LGPL). This document attempts to lay out what this means.

The goal of Shtoom's license is to make sure that all changes and
improvements to the shtoom code are released back to the community.
Any additional code that merely uses the shtoom code is free to remain
closed, open, or whatever the author of the code wants to do.

Essentially, what this means is that if you make changes or additions
to any of the source files that are distributed as part of shtoom,
you *must* make those modified source files available. If you write
new modules, you're free to do with them what you will (obviously, if
they're the sort of thing that's going to be useful to a lot of people,
I'd encourage you to consider contributing them, but that's your call).

The rationale for this licensing is that SIP is a complex beast, and
there's many, many implementations of it. I only have access to a
fraction of these, which makes it hard to do interoperability testing.

I am open to adopting another license and making the shtoom code dual
licensed, so long as it fulfills the goal I've listed above. An MIT or
BSD style license is not acceptable, as it doesn't do what I want.