[NEW] Mail-in admin can specify a namespace, which will be added to all incoming email. Can be used to prevent overwrites.
[ENH] Add some descriptions to the mail-in admin options

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@46358 b456876b-0849-0410-b77d-98878d47e9d5
[NEW] Added check for tiki-mailin option "Allow admin access" in tiki-admin_security.php

git-svn-id: file:///var/local/code.tiki.org/tikisvn/trunk@46359 b456876b-0849-0410-b77d-98878d47e9d5