UX fixes on Configure > Security Policy pages
UX fixes on Configure > Security Policy pages

1) Currently, after selecting an entry in hierarchial drop-down of
firewall Rule create page, there is an extra row getting added as
attached in screenshot

2) Multiple vertical scroll bars in Firewall Policy Popup

Closes-Bug: #1736235
Change-Id: I7e03bc0bc76cfe2a017735690f665c9f62708bbc

biswajit-mandal/contrail-web-controller,biswajit-mandal/contrail-web-controller,biswajit-mandal/contrail-web-controller