Improved locking for possible race conditions on some User limits. Locks will be created under the: /usr/local/directadmin/data/users/username/lock_%s.lock where %s is replaced with the area being worked on. If there are any stray locks (there shouldn't be), will be void after they're 60 seconds old, and will be overwritten by the next process trying to get that lock. ---- Credit: phnix_sec ---- T24245