Migrate dependency from py2 to py3, or moving py2 from Depends to Suggests in control file

[Wei Tsui]

Ubuntu base are supposed to depends on Python3 but Python2, but openvswitch depends on it and core os must install it for no reason. So removing OVS dependency of python2 is strongly recommended.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: openvswitch-common (not installed)
ProcVersionSignature: Ubuntu 4.4.0-22.40-generic 4.4.8
Uname: Linux 4.4.0-22-generic x86_64
ApportVersion: 2.20.1-0ubuntu2.1
Architecture: amd64
CurrentDesktop: GNOME-Flashback:Unity
Date: Thu Jun 9 14:51:58 2016
JournalErrors:
 Error: command ['journalctl', '-b', '--priority=warning', '--lines=1000'] failed with exit code 1: Hint: You are currently not seeing messages from other users and the system.
       Users in the 'systemd-journal' group can see all messages. Pass -q to
       turn off this notice.
 No journal files were opened due to insufficient permissions.
SourcePackage: openvswitch
UpgradeStatus: No upgrade log present (probably fresh install)

[James Page (james-page)]

Python3 is only supported for ovs 2.6.0 (yet to be released but should make 16.10)

[Wei Tsui (ghostplant)]

Why openvswtich-switch package in ubuntu:yakkety still depends on python2 libraries?