Separate Configuration from Freescale SDN ML2 mechanism Driver

- In the current implementation, CRD configuration is existing
  within the code of ML2 mechanism driver.

- When any other plugin/driver (like, Freescale FWaaS Plugin) need
  to use this configuration, it needs to duplicate the complete configuration.

- So the CRD configuration is moved to a separate file for use
  in other plugin/drivers.

- Unit testing of this MD is also updated.

Closes-Bug: #1368033

Change-Id: I488fee47803a494aae9df42f9c59fffa9843e727
Merge "Separate Configuration from Freescale SDN ML2 mechanism Driver"