Add validation on network configuration screens

[Vernal]

We should move the toggle button to the bottom and only enable it when all api form fields are filled out. Or maybe we even get fancy and build in a step to test before enabling.

[ronalfy]

I honestly am just a fan of plain old checkboxes, but that's just me. When I click the toggle, I expect it to be saved automatically for me, as is with iOS.

My 2 cents.