[xDai] - Documentation

[fernandomg]

• Write down the documentation with the required steps to add a new network.
• If there's any other documentation, please add it to this list...

[Agupane]

I added some docs here, please could you review them?
@fernandomg @dasanra @nicosampler

[fernandomg]

Looking nice @Agupane, I just left some observations.

Regarding the location of the md file. Where we'll put it?

Shall we create a /docs directory? or given this case just add it in the src/config/networks directory?

[Agupane]

Yes I wanted to ask the same, I think adding a /docs would be ok but both options are ok for me

[nicosampler]

Looking nice @Agupane, I just left some observations.

Regarding the location of the md file. Where we'll put it?

Shall we create a /docs directory? or given this case just add it in the src/config/networks directory?

I'm fine with both alternatives, just let's add a link from the main Readme.md if not, no one will know this file exists.