Merge local .env when downloading Development Environment Variables

[wyeo]

That would be good

[coetry]

We want to have development env vars synced in the cloud so that it can be distributed to collaborators in a secure way without having to check them into source control.

[styfle]

Put another way, you should not be editing your .env file manually.

Instead use now env add and then now env pull.

Then everyone working on the same project can do git pull followed by now env pull to stay in sync with the latest changes.