Remove Mailchimp

[kylepolich]

Mailchimp is too expensive and we are going to get rid of it. Please make minimal code changes which call our own API instead of mailchimp. We have user/add in the API. Call this and add new parameter. Currently, you must send email and password. Also include src='email_signup'.

Acceptance criteria

• Mailchimp is remove from the entire codebase (library, references, etc)
• Users experience is 100% the same, only backend changes
• Code changes are as minimal as possible
• Signing up on contact-us page or via the pop-up when scrolling to the bottom are confirmed in the database via the API

[Heartless49]

@kylepolich
Continuing from our conversation yesterday about a notification for the user when subscribing, we have two options currently; either a toast notification, or a small text notification.

Both of these are about ready, just need to decide on which one. Here are screenshots of both to help with making a decision.

Toast Notification:

Text Notification:

[Heartless49]

Oh, and the "blank password" concept seems to be working fine at the moment - I'm getting proper responses from the API (used my personal email to sign up and got a 200, "new user signed up" response, whereas when trying again, or with my dataskeptic email, it responds with a 200, "user already signed up" response.

[kylepolich]

@Heartless49 sounds good, please make a PR