WIP 178 Fix Devise Email From Address

WIP: https://assemblymade.com/helpful/wips/178

This PR changes the email address in the devise initializer to "Helpful <noreply@OUTGOING_EMAIL_DOMAIN>" where OUTGOING_EMAIL_DOMAIN defaults to "helpful.io" but can be overridden in .env.

It also makes INCOMING_EMAIL_DOMAIN in .env optional (commented out) since it serves as an override for the default (set in config/initializers/01_env.rb).

Lastly, it forces the env.rb initializer to be loaded first by renaming it to 01_env.rb, this ensures that all values exposed by env.rb are available in later initializers.