Upgrade image-proxy to latest master
Upgrade image-proxy to latest master

Sinar/popit,mysociety/popit,Sinar/popit,Sinar/popit,mysociety/popit,openstate/popit,mysociety/popit,Sinar/popit,mysociety/popit,openstate/popit,openstate/popit,mysociety/popit,openstate/popit