Change error message for missing time limit

Error message changed from
Missing time limit
to Job submission rejected due to missing time limit
bug 438

src/common/slurm_errno.c

@@ -397,7 +397,7 @@ static slurm_errtab_t slurm_errtab[] = {
 
 	/* plugin and custom errors */
 	{ ESLURM_MISSING_TIME_LIMIT,
-	  "Missing time limit"                                  }
+	  "Job submission rejected due to missing time limit"   }
 };
 
 /*