help-orterun.txt: minor word smything

Signed-off-by: Jeff Squyres <jsquyres@cisco.com>

orte/tools/orterun/help-orterun.txt

@@ -642,14 +642,13 @@ number of processes to run:
 Please correct this value and try again.
 #
 [orterun:timeout]
-The user-provided time limit for job execution has been
-reached:
+The user-provided time limit for job execution has been reached:
 
-  MPIEXEC_TIMEOUT: %d seconds
+  Timeout: %d seconds
 
 The job will now be aborted.  Please check your code and/or
-adjust/remove the job execution time limit (as specified by
-MPIEXEC_TIMEOUT in your environment or --timeout on the command line).
+adjust/remove the job execution time limit (as specified by --timeout
+command line option or MPIEXEC_TIMEOUT environment variable).
 #
 [orterun:conflict-env-set]
 ERROR: You have attempted to pass environment variables to Open MPI