Pass custom docker-machine flags to `dinghy create`

[manojlds]

trafficstars

With docker-machine, I am able to pass the argument --engine-insecure-registry <registry> when creating the vm.

[manojlds]

Current workaround is to set EXTRA_ARGS with --insecure-registry in /var/lib/boot2docker/profile and restart the docker-machine.

[codekitchen]

You could always create the machine directly by calling docker-machine create <opts...> dinghy, but for ease-of-use maybe it's worth adding the ability to specify custom docker-machine create flags when calling dinghy create, something like dinghy create -p virtualbox -- --insecure-registry XX

[danny-balance]

:+1: for custom flags on dinghy create

[mrwilby]

+1 Would be useful

[jeffgran]

:+1: