Feature request: add CloudFlare tunnel

[tpjanssen]

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Is your feature request related to a problem? Please describe.

Currenty there is no way to connect to a CloudFlare tunnel. This function is definitely an added value for systems connected to the internet by means of CGNAT.

Describe the solution you like

A function to setup and manage a CloudFlare tunnel through the web interface.

Describe alternatives you considered

It is possible to do this on the CLI (by installing cloudflared manually), but this is not preferable.

Additional context

N/A