Remove deprecated features no longer supported by Mailchimp

[jeffpaul]

Conversely to #6, there are items that no longer are required as part of this plugin and should be removed/deprecated accordingly:

• deprecate/remove Monkey Rewards
• confirm w/Mailchimp on other features/copy/etc. to deprecate/remove (will be confirmed post-kickoff discussions)

[dkotter]

Talking with Mailchimp today, sounds like the only thing right now that needs removed is Monkey Rewards.

I would say probably good for us to keep our eyes open as we go through the code for other things that seem to no longer be used and we can bring those to the Mailchimp team to get their thoughts.