feat: support julian day timestamp value conversion to datetime.datetime #1948

[erenkeskus]

I have added float casting as discussed in the issue to be able to support from julian day format.
Fixes #1948 🦕

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[Linchin]

Cheers! Could you

• sign the CLA that's linked in this comment, so we can legally merge your code
• Add a unit test here, you can use adjacent methods as a reference

Thanks for your help :)

[chalmerlowe]

@erenkeskus @Linchin

Before we move forward with this, I have a number of questions. See Issue #1948 associated with this PR.

I added the Do Not Merge tag to prevent merging this until we ensure that we are on the same page.

Please discuss in the Issue. Thanks.