Replace MailChimp form with HubSpot

[noman-land]

Differences from original version:

• Validation happens at HubSpot now so no more validation animations and error messages are different
• Couldn't get the placeholder text color to match the original :\
• Spacing on the post-submit thank you message has been tightened up

Before

After

Here is the form where the submit button, placeholder text, and thank you message can be customized.

@oskarth