Adding more details to documentation [How are my calendars sync].

Hi team, could you please add some more details about where the sync is coming from in better detail in the doc https://help.hospitable.com/en/articles/6124538-how-are-my-calendars-synced-and-how-do-i-tell-where-data-is-coming-from?

It currently doesn't say what "reservation sync" or "airbnb" means. So it would be nice to have those there and would help the smarty bot too.
May be in a table format so it would look nicer.

Thanks