DNS help improvements

We've made additional quality-of-life improvements to our inline help documentation when a DNS change is required:

• Detect common forwarding services based on IP address and inform that these first need to be disabled.
• Improved copy.
• Added label to some IP addresses if they are communicated differently in the DNS zone editor.

On top, we've been also been busy on other segments:

• Added better error handling to our tester to inform you
• Improved the performance of the SSL certificate installation.
• Some mobile styling improvements in-app.