[Evolution] spool, maildir, and other stuff.

[Not Zed <notzed ximian com>]

I've setup some code so you can now setup a base maildir directory and
have them show up as a separate store (similar to imap, an account name
and then a tree of subfolders).  They dont show up very pretty and maybe
the subdirectory searching isn't correct, however it should basically
work at the camel level; the ui definetly needs more cleanup.  Trash
doesn't seem to work right though.

I have done a similar thing for the new 'spool' provider, you can now
setup mail spools (and other external mbox compatible files) as a native
folder.  It mostly seems to work ok right now, detects new mail, etc.
Well it operates with my inbox in elm about as well as can be expected.
It now does locking as required too, and as a bonus it locks properly
(no permission problems) with the default mail spool settings in redhat
and whatnot.  Again the ui is a bit funny, and the trash doesn't work
yet with this either.

None of the other stuff should be affected, although I made a change to
camel url's usage in the mailer code that permits subfolders to work
with maildir/etc.  This uses the fragment to store the path; if we have
no fragment i still use the path as the path, so imap folders should
still work properly (this is partially why the trash breaks for spool
stores i think).

I'll be changing the movemail code to use the new locking daemon
tommorow I guess, so hopefully that doesn't break anything either (just
a little heads up incase it does).  The daemon probably needs some extra
securing/validation but it is fairly small so should be easy to check.
The makefiles only need to set it to install at the mimimum security
level for a given system anyway, e.g. like setgid mail on redhat, which
needs to be fixed as right now i just install setuid root.

 Michael