Improvements to flows list command.

 * Added -s option which gives more succinct output.
 * Display each flow on one line for easy grepping.
 * Added ability to filter output by table ID.
 * Flows are now sorted by descending priority within a table.
 * Removed the use of toStringHelper in instructions and criterion to produce
   less verbose output.

Change-Id: I1c874c776491386488ea5a4d23627b20f1e5728b
diff --git a/cli/src/main/resources/OSGI-INF/blueprint/shell-config.xml b/cli/src/main/resources/OSGI-INF/blueprint/shell-config.xml
index 59ebeb2..f9dde70 100644
--- a/cli/src/main/resources/OSGI-INF/blueprint/shell-config.xml
+++ b/cli/src/main/resources/OSGI-INF/blueprint/shell-config.xml
@@ -427,6 +427,8 @@
             <completers>
                 <ref component-id="flowRuleStatusCompleter"/>
                 <ref component-id="deviceIdCompleter"/>
+                <ref component-id="placeholderCompleter"/>
+                <null/>
             </completers>
         </command>