[openvswitch] Add new plugin

This splits out the ovs collection data from the Neutron plugin.

Fixes #328

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
[ubuntu] rename from ubuntu-support-status

In an attempt to keep distro specific collection (ie ubuntu-support-status)
create a general `Ubuntu` plugin to categorize this information. This will
be the default for other distributions needing to do the same.

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>
[dbus] new dbus plugin

Adds dbus plugin support for Fedora, Debian, and Ubuntu. Also pulls the
`/var/lib/dbus/machine-id` out of general into this plugin.

Fixes #350

Signed-off-by: Adam Stokes <adam.stokes@ubuntu.com>