Make router-interface-delete work in N1kv plugin

Fixes bug 1226729

Change-Id: If2c6bc544dfa45cb98d5951c99f158d49191b031
BigSwitch plugin: allow 'external' keyword in router rules

Allows 'external' keyword in addition to 'any' keyword
in BigSwitch router rules support.

Closes-Bug: #1226814
Change-Id: Ia92513e89b0c95c5b3b98921e126fdd21cc4f405
Merge "Make router-interface-delete work in N1kv plugin"
Merge "BigSwitch plugin: allow 'external' keyword in router rules"