Tuple to single value traits

[joshqsumner]

Describe your changes
Outputs ellipse_center and center_of_mass as single _x and _y traits instead of tuples.

Type of update
Is this a feature update.

Associated issues
Closes #1666

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• PR functionality reviewed in a Jupyter Notebook
• All tests pass
• Test coverage remains 100%
• Documentation tested
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[deepsource-io]

DeepSource Code Review

DeepSource reviewed changes in the commit range c5454ac...386f4be on this pull request. Below is the summary for the review, and you can see the individual issues we found as review comments.

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PR Report Card

Security	× 0 issues		Overall PR Quality
Reliability	× 0 issues
Complexity	× 0 issues
Hygiene	× 0 issues
Coverage	× 0 issues

Code Review Summary

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Python		No new issues detected.	Review ↗
Test coverage		No new issues detected.	Review ↗

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Language	Line Coverage		Branch Coverage
	New Code	Overall	New Code	Overall
Aggregate	100% [✓ above threshold]	100%	100%	100%
Python	100% [✓ above threshold]	100%	100%	100%

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[HaleySchuhl]

Feel free to disagree, what if tuples were output in both CSVs (for backwards compatibility with statistical workflows downstream)?