Add Tutorial For Datetime Data

[noorbuchi]

This PR is WIP

This tutorial will help users understand how to plot data in date and time ranges. It will discuss the different possible formats of the data and give examples of how the plots can be customized. Many community members mentioned the need for this tutorial so our team (@munzekm, @cklima616, @nathandloria and I) will working on it.

Fixes #549

Reminders

• Run make format and make check to make sure the code follows the style guide.
• Add tests for new features or tests that would have caught the bug that you're fixing.
• Add new public functions/methods/classes to doc/api/index.rst.
• Write detailed docstrings for all functions/methods.
• If adding new functionality, add an example to docstrings or tutorials.

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• /format: automatically format and lint the code
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