Added the '-Q' quiet flag announcement to the RELEASE_NOTES

RELEASE_NOTES

@@ -33,6 +33,8 @@ CONFIGURATION FILE CHANGES (see "man slurm.conf" for details)
 COMMAND CHANGES (see man pages for details)
 * Several redundant squeue output and sorting options have been removed: 
   "%D" (use %o"), "%b" (use "%S"), "%X", %Y, and "%Z" (use "%z").
+* Standardized on the use of the '-Q' flag for all commands that offer the
+  --quiet option.
 
 
 OTHER CHANGES