OMP::General: avoid use of alarm when locking log

Using an alarm to implement a timeout for the log file locking
procedure is problematic for the Queue.  Therefore the alarm
has been removed, and in its place is a loop which spends 5 seconds
trying to acquire the lock in a non-blocking manner.

See faults 20140812.009 and 20120131.003.
Merge branch 'master' into summit