Add guide for new io formats

[felixdivo]

This adds a guide on how to add new file format support.

Added in response to #506.

[danielhrisca]

@felixdivo

each Writer is meant to handle a single bus channel? For example if we have a vector HW and we use bus channels 0 and 1 then the used should instantiate two Write objects for each of them?

[codecov]

Codecov Report

Merging #548 into develop will not change coverage.
The diff coverage is n/a.

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  Misses        2009     2009

[felixdivo]

Writers are just dumb can.Listeners, which receive messages in the on_message_received() method. The writer does not care about the bus that this message came from or how it was brought there, except maybe that the Message.channel attribute is set that then gets serialized. So there may be zero to many writers serializing the messages of zero to many buses. Distributing is often done by using a Notifier. Does that answer you question?

[danielhrisca]

I got the point. I'll think about a strategy to handle this

[hardbyte]

Fantastic guide!

Please consider a few suggested changes.