Feat: Add Automations / Email Sequence or Drip Campaigns

Would be great if the app supports adding a basic automation feature so send email sequences or drip campaigns  with a delay. 

eg:

```
    Contact created
             ⇓
    wait 20 minutes
            ⇓
Send Welcome email
             ⇓
      Wait 2 days
             ⇓
    Ask for feedback

```