Rename Queue related methods for VMware NSX plugin

This is the first step of many for renaming/refactoring
nvplib and related modules. Starting with queues, whose
code is small and less daunting.

Partial-implements blueprint: nicira-plugin-renaming

Change-Id: I2db899883c61f30c8b15703c96290872e853d670
Merge "Rename Queue related methods for VMware NSX plugin"