[12448] Calendar, some hotfixes. Correct player guid usage for sql request. (use GetCounter() instead of GetString()) Correct CMSG_CALENDAR_REMOVE_EVENT handler. Correct some possible crash. Use a better way to add element in EventsStore map. Correct sql update and revision.

Thank for all your feedback its a pleasure for me to recieve it they will make me better :)

(based on commit [12339] - dc7fd39)