Did following changes
1)Added the flag based on which the topology changes will be displayed in UI
2)Added the direction column in the trace flow grid and picking vrouter ip based on the direction and some minor bug fixes

Change-Id: I3a5a13b2a6457d14c02c6bec8e7155aae8fb1206
Merge pull request #11 from vishnuvv/Underlay

Did following changes