Temperature unit

[adamdempsey90]

Dealing with an issue in Artemis, flipping this fixes it. I think this is consistent with how the mass, time, and length units are interpreted in this function.

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[adamdempsey90]

Reminder to add simple unit test

[buechlerm]

relative to the densithy and sie, this looks correct. Users may need to make changes on their end.

[adamdempsey90]

Yeah, just like the original commit that changed this, this will be breaking

[Yurlungur]

Thanks for the fix. I think this was an incomplete fix from before. I won't block the merge, but should we add a test? If not, just push back and I'll click merge.

[adamdempsey90]

Thanks for the fix. I think this was an incomplete fix from before. I won't block the merge, but should we add a test? If not, just push back and I'll click merge.

Test added. I pulled the exact values from Artemis that were causing the issue. If you switch 1. / temperature to temperature in the UnitSystem creation, the test will fail.

[Yurlungur]

Assuming tests are passing on re-git, merge when ready