1. instead of using inboxcount as the core message counting function, we use messagecount instead. This makes it possible to count messages in folders besides just INBOX and Old.
2. inboxcount and hasvoicemail now use messagecount as their means of determining return values.
3. Added a copy_message function for IMAP storage. Unfortunately I don't have the means to test it, but it seems like a pretty straightforward function.
4. Removed a #ifndef IMAP_STORAGE and matching #endif from leave_voicemail for a couple of reasons. One, we want to support copying mail to multiple IMAP boxes, and two, IMAP was
broken because a STORE macro had been moved into this section of code.
git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.4@78859 65c4cc65-6c06-0410-ace0-fbb531ad65f3