Fixed Issue #207:
Implement remaining API for getting flow state

NOTE: The implementation of the API backend is sub-optimal,
but should be sufficient for now:
  We fetch all flows, and then return only the subset that match
  the query conditions.
  We should use the appropriate Titan/Gremlin query to filter-out
  the flows as appropriate.

Estimated: 2D
Actual: 1D
diff --git a/src/main/java/net/floodlightcontroller/flowcache/IFlowService.java b/src/main/java/net/floodlightcontroller/flowcache/IFlowService.java
index c14c0c1..b159661 100644
--- a/src/main/java/net/floodlightcontroller/flowcache/IFlowService.java
+++ b/src/main/java/net/floodlightcontroller/flowcache/IFlowService.java
@@ -41,15 +41,15 @@
     FlowPath getFlow(FlowId flowId);
 
     /**
-     * Get a previously added flow by a specific installer for given
+     * Get all previously added flows by a specific installer for a given
      * data path endpoints.
      *
      * @param installerId the Caller ID of the installer of the flow to get.
      * @param dataPathEndpoints the data path endpoints of the flow to get.
-     * @return the Flow Path if found, otherwise null.
+     * @return the Flow Paths if found, otherwise null.
      */
-    FlowPath getFlow(CallerId installerId,
-		     DataPathEndpoints dataPathEndpoints);
+    ArrayList<FlowPath> getAllFlows(CallerId installerId,
+				 DataPathEndpoints dataPathEndpoints);
 
     /**
      * Get all installed flows by all installers for given data path endpoints.