README.md: Add tested features on Duet 5

[jhonnystene]

Pen input confirmed working (with less latency than in ChromeOS!) using Krita. Positioning seems accurate, pen pressure working.

Front and back camera are in /dev/video* but can't actually be opened as real cameras (tested in Cheese).

Suspending and resuming worked perfectly with my testing.

[hughwilliams94]

I think those devices in /dev/video are the Qualcomm Venus decoder/encoder right, not the cameras?

[jhonnystene]

Webpage not available

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  h2   { margin-top: 5px; padding-top: 0px; }


Entirely possible I missed that, I'll take a closer look later this week.