* root: make global email settings configurable
* stages/email: add use_global_settings
* stages/email: add test_email command to test email sending
* stages/email: update email template
* stages/email: simplify email template path
* stages/email: add support for user-supplied email templates
* stages/email: add tests for sending and templates
* stages/email: only add custom template if permissions are correct
* docs: add custom email template docs
* root: add /templates volume in docker-compose by default
* stages/email: fix form not allowing custom templates
* stages/email: use relative path for custom templates
* stages/email: check if all templates exist on startup, reset
* docs: add global email docs for docker-compose
* helm: add email config to helm chart
* helm: load all secrets with env prefix
* helm: move s3 and smtp secret to secret
* stages/email: fix test for relative name
* stages/email: add argument to send email from existing stage
* stages/email: set uid using slug of message id
* stages/email: ensure template validation ignores migration runs
* docs: add email troubleshooting docs
* stages/email: fix long task_name breaking task list
Marc 'risson' Schmitt
Jens Langhammer
Jens L
Felix Eckhofer