Add plumgrid vif driver
Add plug and unplug definition for PLUMgrid plugin
Add condition for vif_type plumgrid in nova vif driver
Add native delete tap interface method
Include rule in vif driver
Moves Hyper-V options to the hyperv section

Fixes Bug: 1140778

Due to the large number of options available in Nova, in order to
achieve better option organization and naming (e.g. avoid the hyperv_*
prefix) and to avoid option name clashes, options specific to the
Hyper-V driver are moved to a section named "hyperv".

Backwards compatibility is mantained by providing the "deprecated_group"
argument in option definitions.

For case consistency the group name as been changed to "hyperv" for options
introduced in Grizzly belonging to the group "HYPERV"

Change-Id: If2710822cdf6e4ae108a6d1e7977735ac8104a2e
Replace rule value with proper variable
Creates the proper pgtags for EVO platform
Fix ifc command using gateway instead of .