Add toggle to enable/disable site verification

[MichaelArestad]

Let's add a toggle to enable or disable Site verification. This is a little tricky considering the UI required for site verification.

Here's a basic mock:

When the module is disabled (toggled off), should we show the content and form fields? I lean toward yes as long as they are disabled. Thoughts?

The other option would be to simply hide the content under the toggle when it is deactivated. That would be tidier for sure.