[Dovecot] Allowing tilde at start of mailbox names

[pod]

>>>>> "TS" == Timo Sirainen <tss at iki.fi> writes:

    TS> How about if listescape plugin escaped it? That would make it
    TS> possible to use them but still safe against accidental problems.

Yes, I think that would work fine at least for my particular purposes
since we'll almost certainly be running with the listescape plugin anyway.

    TS> For others too, I implemented a plugin for escaping mailbox names
    TS> with Maildir so that it's possible to use '.' in mailbox names:
    TS> http://dovecot.org/patches/1.0/listescape-plugin.c

Not one to blow your own trumpet are you!  For further explanation for the
benefit of the list: I recently contacted Timo privately asking if he
would consider us funding him to implement a modified maildir layout for
us.  A few hours later he responded with listescape-plugin.c.  What an
absolute star.