Update the pop-up shown on initial visit and the FAQs

[gravenp]

We should provide more explicit guidance for those just getting started with the Geo Web to improve their onboarding experience.

Requirements

• Replace the "Beta Warning" pop-up shown with a "Welcome Checklist" one:
  • See desktop mock-up (mobile will require scrolling)
  • Show this pop-up to all first-time users
  • Copy/paste text & links are available here
  • Open all links in a new tab
• Update the FAQs module with new text. Changes are shown as suggestions here.