cyrus-imapd-2.2.11: update imapd annotate extension to eliminate single byte overflows.

do bounds checking on backend socket path.
do bounds checking on fetchnews LIST ACTIVE reply.
do string length checking on mailbox name during DELETE when virtual domains are in use.
fix single byte overflow in RENAME.
fix single byte overflow in cached header handling.
do string length checking in mailbox name operations when virtual domains are enabled.
fetchnews has a buffer overflow explotable by a foreign