tools: exit with non-zero on advertise/withdraw error

refs #5271

Change-Id: I287fc5746ac1fd2930bb85ac49e5ad732abd3581
diff --git a/docs/manpages/nlsrc.rst b/docs/manpages/nlsrc.rst
index 81d92f2..7b566b4 100644
--- a/docs/manpages/nlsrc.rst
+++ b/docs/manpages/nlsrc.rst
@@ -90,4 +90,5 @@
 nlsrc exits with one of the following values::
 
   0     nlsrc exited successfully
-  >0    An error occurred
+  1     generic error
+  2     bad command line