Document "common parameters"

[jasmingacic]

https://www.packet.com/developers/api/#common-parameters The documentation doesn't have anything about exclude and only which are currently supported by the API.

[displague]

A generated client would give us this: https://github.com/displague/metal-python/blob/8d980e8148425fc866141b14704659cfcf48b1b8/docs/FacilitiesApi.md#find_facilities_by_project (#106 )