Related-Bug: #1390392
Related-Bug: #1390392

Added prefixToNetmask

Change-Id: I93c8ff9a8ecf8660b6a5064a56f57c16c32b4313

biswajit-mandal/contrail-web-core,vishnuvv/contrail-web-core,nagakiran/contrail-web-core,hari-sk/contrail-web-core,hari-sk/contrail-web-core,nagakiran/contrail-web-core,biswajit-mandal/contrail-web-core,vishnuvv/contrail-web-core,hari-sk/contrail-web-core,biswajit-mandal/contrail-web-core,vishnuvv/contrail-web-core,nagakiran/contrail-web-core