Readme updates

[samwalkow]

This is a pull request that contains changes to the readme and adds two new markdown files with examples that include loading, subsetting, and plotting data. Those are in the examples folder.

[chrishavlin]

Oh! forgot to mention: I like the .md examples. It's nice to have those plain-text examples. One tricky thing is that as development happens, it's easy for those sorts of files to become out of date (e.g., say we update the schema, we have to remember to go update all those examples). But once we have a full documentation, we can dynamically embed examples more easily -- so you could move the json bits into their own json files and then we would embed those in the docs. That allows us to write tests that actually run all the example jsons to make sure they continue working.

[chrishavlin]

@samwalkow this looks good to me, did you want to add anything else here? shall I merge?

[matthewturk]

Will it be up by the time the package is published?

[matthewturk]

Suggested change

	Currently, the Analysis Schema is built from [yt](https://github.com/yt-project/yt), a python library for analyzing and visauliation volumetric data. It also uses [pydantic](https://github.com/pydantic/pydantic) to create the schema and validate workflow input.
	Currently, the Analysis Schema is built for [yt](https://github.com/yt-project/yt), a python library for analyzing and visauliation volumetric data. It also uses [pydantic](https://github.com/pydantic/pydantic) to create the schema and validate workflow input.

[matthewturk]

Aren't we on BSD 3-Clause?