[Dovecot] Use Solr for LMTP

data/conf/dovecot/dovecot.conf

@@ -283,7 +283,7 @@ protocol imap {
 }
 mail_attribute_dict = file:%h/dovecot-attributes
 protocol lmtp {
-  mail_plugins = quota sieve acl zlib listescape mail_crypt mail_crypt_acl
+  mail_plugins = quota sieve acl zlib listescape mail_crypt mail_crypt_acl fts fts_solr
   auth_socket_path = /usr/local/var/run/dovecot/auth-master
 }
 protocol sieve {