[PATCH] Maildir folder and courier Maildir++ support (quota)

[sirius]

I have extended the twisted maildir implementation with folder support and the
courier maildir++ extension(quota). All maildir functionality is now
concentrated within a single (new) class called Maildir. The included patch also
updates the testcase for maildir support. I have tried to keep things as
backwards compatible as possible. The patch was developed for twisted-1.1.0, but
it currently also applies without errors to the CVS version.

I'm new to the Twisted project, so I would be very happy if you guys could give
some comment on this piece of code. I'm still testing it and I'm about to use it
in the project I'm actually working on.

[radix]

exarkun's probably the person this is most relevant to.

[exarkun]

I reviewed this patch shortly after it was submitted, but did not finish and
couldn't decide on the proper response.

I think that most of the functionality this patch provides is useful, but I'm
not certain how it is useful to Twisted.  I now think the best way to proceed
would be to provide this Maildir implementation as a standalone module that
implements a well defined interface, and then, if necessary, patch Twisted to
support objects of that interface.

[exarkun]

Doing that, then.