this patch includes some plumbing for the nsx v3
port security port which will come in subsequent
patches. in particular this patch refactors the nsx v3
nsxlib rest client and adds a rest resource for nsx v3
switching profiles which will be leveraged in port
security implementation. unit tests included.
Change-Id: I210c8cc495bf30c798445c20f9604689fea37521
a7c909536e