Updates for Alpha 7

[asoltys]

This pull introduces the following aesthetic features/fixes:

• Partition the list of exits by Registered/Viable/Nonviable and differentiate between connection and registration
• Placeholder icons from react-fontawesome component library to indicate detailed connectivity status (to be improved following UX design)
• Fix bug with settings not being fetched after selecting an exit that made the selection lag
• Run prettier on the codebase and configure eslint
• Wire up the wifi mesh toggle checkbox on the router settings page to the form state and put in a stub for the backend
• Put the Althea logo in the navigation bar and highlight the currently selected page
• Temporarily hide links to the Payments page

[jkilpatr]

tested on my routers, works