Number of sent messages of various types in MyChat

All indicators (except MyChat Guest) count from the moment of the server start and reset on the start or restart.

Private	number of sent private messages;
Conferences	total number of sent messages in all conferences;
Announcement board	number of published messages on the announcement board;
Broadcasts	number of sent multi-user messages;
MyChat Guest invitations	total number of sent external invitations to the chat.