Skip warning prompts in migrations when not in a TTY

[sneak]

Pitch

First installs incur 3 different 10s delays applying initial database migrations. It would be awesome if first installs could set an environment variable to skip these delays when deploying new instances.

[sneak]

Perhaps it could be even simpler: check to see if stdout is a tty, and skip the countdown if it is not (e.g. during migrations from a startup script).

[Gargron]

Don’t use db:migrate for first installs! db:setup is faster! It uses db:schema:load which just creates the latest schema right away instead of running migrations one by one

[sneak]

Well, it shouldn't do a 10s delay in any case even for a migration if stdout is not a tty.