Add Channel callback + reading isFavourite

[biokys]

To be able to read channel metadata like role and name, I added channel callback.

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[fifieldt]

Thanks @biokys ! If you can sign the CLA, this seems good to go: https://cla-assistant.io/meshtastic/Meshtastic-arduino?pullRequest=34

[biokys]

Thanks @biokys ! If you can sign the CLA, this seems good to go: https://cla-assistant.io/meshtastic/Meshtastic-arduino?pullRequest=34

I have already agreed the agreement. Several times, but there is still pending state. Cant be any issue there?