Fix wrap target in iptables_manager

This patch fixes issues when using wrap target
for add_rule and remove_rule methods.

Change-Id: I01926719ef5ccf229748b9ceb1553e5314ab623e
Closes-bug: #1269189
Rename/refactoring of NVP api client to NSX

Partial-implements blueprint nicira-plugin-renaming

Change-Id: I7d3bc088762f53473892480b2e238fe60c2c0b74
Merge "Fix wrap target in iptables_manager"