Config-enabled ordering on subscriptions

[ethan-fox]

Hello,

I'm having trouble tracking down how we might toggle ordering for a given subscription we specify as environment configs.

It's my understanding from the docs that ordering is supported for the Pubsub emulator but based on the source code I'm not seeing how we might be able to specify this with configs.

For my immediate need I could manually spin up the subscription in a script and apply ordering that way, but seeing as my development environment heavily uses docker-compose it would be nice if this kind of thing was supported out of the box.

Happy to draft a proposal/PR myself but I was just wondering if I'm missing something.

Thanks!

[ethan-fox]

I first described the issue in marcelcorso/gcloud-pubsub-emulator#22 but upon further review i believe the issue is best tackled here (and possibly coordinated with upstream?)