Log tools improvement

- Add 'olo' command to filter log of remote ONOS instance
- Modify 'onos-log' such that it can run on OSX

Change-Id: Iddab996564af01672c14caca725397c574267bad
diff --git a/tools/test/bin/onos-log b/tools/test/bin/onos-log
index b8c5bf4..6e1d142 100755
--- a/tools/test/bin/onos-log
+++ b/tools/test/bin/onos-log
@@ -31,7 +31,7 @@
     while true; do
         echo ==================================================================
         [ ! -f $LOG ] && sleep 2 && continue
-        tail -n 512 --follow=name $LOG --pid \$$ --sleep-interval 2
+        tail -n 512 -f -F $LOG
     done
     "
 fi