Covers: Request for additional inverted cover-entity

[wach22]

Hi there, this is a great integration! 👍

I know there has been sufficient debate already about the mismatch definitions of open vs closed position of cover entities between Rademacher and Home Assistant. I understand that this integration follows HA's definition. Nevertheless, that's quite confusing ... 😢

I would like to support the suggestion in #111:
Why not adding a second cover entity for each Rademacher cover device, which shows the inverted position?
Okay, this is some redundancy but this way, everyone could pick his preferred mode.
To avoid confusion, this second inverted cover entity could be de-activated (hided) in the standard integration and one can individually activate it when deemed appropriate.