scripts: Added glide-update script
scripts: Added glide-update script

To make updates of the dependencies easier I have added this script, now it's
just a single command to update the deps and clean unused packages.

dgonyeo/docker2aci,dgonyeo/docker2aci,vishvananda/docker2aci,appc/docker2aci,appc/docker2aci,OMWAVE/docker2aci,OMWAVE/docker2aci,vishvananda/docker2aci