Add an onboarding guide URL to end device definitions

[KrishnaIyer]

Summary

I propose to add an onboarding guide URL to end device definitions.

Why do we need this?

To have a link to a document where users can get very specific and direct guide to onboard a particular device.

What is already there? What do you see now?

We currently have a productURL which seems like it's for general product description/marketing and and dataSheetURL which usually has a lot of technical information.

What is missing? What do you want to see?

A onboardingGuideURL that points to documentation that specifically has steps to onboard the device.
Ex: Download App -> Set Params -> Insert battery -> device should send a join request.

We can help device manufacturers with a nice "template" for this in our docs, if they choose to use it.

How do you propose to implement this?

I'll leave that to @LDannijs. Let's first discuss if this is something we'd like to do.

Can you do this yourself and submit a Pull Request?

No but I can help do E2E testing and also come up with the first few guides.

[johanstokking]

I think this makes sense. Few comments:

1. We don't need all the standard screenshots like in https://www.thethingsindustries.com/docs/devices/models/browan-tbms100/; we should refer to the existing guide only providing the settings that need to be set
2. We need to structure this under the vendor ID as a folder
3. We need to make sure that this is not used to advertise or explain how great the device is
4. Vendors can also choose to put their own URL in there. It doesn't have to be specific for TTS as long as their page is comprehensive w.r.t. LoRaWAN settings

[KrishnaIyer]

Ok great thanks. @LDannijs can you take this forward?

[LDannijs]

Yeah sounds good I'll get on it soon 👍

[KrishnaIyer]

This is closed via #765