Magento 2: Allow forcing maintenance mode

[lfolco]

We are on a hosting provider that does not support zero-downtime deployments, so we need to set maintenance mode on Magento 2 explicitly. Currently the Magento 2 recipe will dynamically check if maintenance mode is needed and set/unset accordingly. The issue is, if we set maintenance mode at the beginning of our deployment, it will get unset during these tasks.

Any chance to have a config to enable this behavior?

[antonmedv]

Why not override whole deploy task?

[lfolco]

I'm trying to avoid overriding, especially considering #2878. I'm not sure what I'll be breaking with an override.