Add notifications tab/section to WP dashboard

[lukefretwell]

Source
The source of the issue (ex: Customer: #CustomerName#).

LF

Is your feature request related to a problem? Please describe.
A clear and concise description of what the problem is. Ex. I'm always frustrated when [...]

Placeholder for adding a notifications tab/section in the WP admin that allows users to manage email related set up:

• MailChimp + Constant Contact integration
• Notifications + (what we currently call ProudCity Notifications)

Describe the solution you'd like
A clear and concise description of what you want to happen.

Describe alternatives you've considered
A clear and concise description of any alternative solutions or features you've considered.

Additional context
Add any other context or screenshots about the feature request here.