Adding a toggle to enable temperature compensation

[purepani]

Currently there is no way to enable the temperature compensation feature of this sensor with this library. It's possible to write to the register directly, but the position of 0mT of the output changes from 0x0 to 0x8000, so it would be helpful for the library to figure out the logic for that instead of doing it manually.

[purepani]

@tekktrik I'm currently implementing this, and I was just wondering how you think it the invalid resolutions for the temperature compensation should be handled.
See https://www.melexis.com/en/documents/documentation/application-notes/application-note-mlx90393-temperature-compensation for details, but basically the temperature compensation is only functional on 16 and 17 bit resolutions, but not higher.

I'm not actually sure what the chip is doing when you have a higher resolution set, but I think the temperature compensation is just not affecting the output. It might be confusing if there's nothing that happens when a user sets the temperature compensation too high though and nothing happens, so I thought I'd go ahead and ask.