Documentation for meta-data and vendor-data

[Pratik-Poojary]

We could not find any document related to meta-data and vendor-data used in autoinstall, when to use one or the other. Please share any relevant documentation related to autoinstall's meta-data and vendor-data with appropriate examples for each of the autoinstall files.

[bash-bandicoot]

meta-data should exist but remain an empty file, user-data is the #cloud-config file