Merge branch 'master' into new-csv-implementation

# Conflicts:
#	core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/convert.kt
#	core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/api/parse.kt
#	core/src/main/kotlin/org/jetbrains/kotlinx/dataframe/impl/io/FastDoubleParser.kt
#	core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/io/FastDoubleParserTests.kt
#	core/src/test/kotlin/org/jetbrains/kotlinx/dataframe/io/ParserTests.kt
#	gradle/libs.versions.toml

Author: Jolanrensen

.github/README.md

@@ -0,0 +1,33 @@
+## GitHub Actions
+
+While publishing and testing of the library is handled by [JetBrains TeamCity](https://www.jetbrains.com/teamcity/),
+there are some CI operations that are handled by GitHub actions instead.
+
+### Publishing Docs
+
+The building of the documentation website in [docs](../docs), and the publishing of it along
+with the search-indices is handled by the [Build Docs GH Action](./workflows/main.yml). Careful: This action replaces the entire contents
+of the documentation website.
+
+### Gradle Wrapper Validation
+
+We run the [Gradle Wrapper Validation action](https://github.com/gradle/wrapper-validation-action)
+using a [GitHub Action](./workflows/gradle-wrapper-validation.yml) as well.
+This action validates the checksums of all Gradle Wrapper JAR files present in the repository and
+fails if any unknown Gradle Wrapper JAR files are found.
+
+### Auto-commit generated code
+
+Anytime the source code changes on [master](https://github.com/Kotlin/dataframe/tree/master),
+this [GitHub Action](./workflows/generated-sources-master.yml) makes sure
+[`processKDocsMain`](../KDOC_PREPROCESSING.md),
+and `korro` are run. If there have been any changes in either [core/generated-sources](../core/generated-sources) or
+[docs/StardustDocs/snippets](../docs/StardustDocs/snippets), these are auto-committed to the branch, to keep
+it up to date.
+
+### Show generated code in PR
+
+To make sure no unexpected code is auto-committed to [master](https://github.com/Kotlin/dataframe/tree/master),
+this [GitHub Action](./workflows/generated-sources.yml) runs the same code-generating tasks but on a separate branch.
+If there are changes, it will leave a message in the PR, informing you about the changes that will be done to the master
+branch if this PR were merged.

core/README.md

@@ -0,0 +1,49 @@
+## :core
+
+This is the core of the library, published as the `dataframe-core` package.
+It contains the DataFrame API and its implementation, as well as plenty of JUnit tests.
+
+I/O operations are split off into other modules, like [:dataframe-excel](../dataframe-excel),
+or [:dataframe-jdbc](../dataframe-jdbc), however, this is has not happened yet for all operations
+(see [Issue #100](https://github.com/Kotlin/dataframe/issues/100)).
+
+At the moment, these integrations are still part of the `:core` module:
+
+- csv/tsv
+- html
+- json
+- jupyter
+
+### Korro code samples
+
+Code samples for the documentation website reside
+in [core/.../test/.../samples/api](./src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api) (for samples that depend solely on `dataframe-core`),
+and [tests/.../samples/api](../tests/src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api) (for samples can depend on other I/O modules)
+and they are copied over to Markdown files in [docs/StardustDocs/topics](../docs/StardustDocs/topics)
+by [Korro](https://github.com/devcrocod/korro).
+
+### Explainer dataframes
+
+Aside from code samples, `@TransformDataFrameExpressions` annotated test functions also generate sample
+dataframe HTML files that can be used as iFrames on the documentation website.
+They are tested, generated, and copied over to [docs/StardustDocs/snippets](../docs/StardustDocs/snippets) by
+our "explainer" [plugin callback proxy](./src/test/kotlin/org/jetbrains/kotlinx/dataframe/explainer),
+which hooks into [the TestBase class](./src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/TestBase.kt) and
+retrieves the intermediate DataFrame expressions thanks to our "explainer" compiler plugin
+[:plugins:expressions-converter](../plugins/expressions-converter).
+
+We can also generate "normal" DataFrame samples for the website. This can be done using the
+[OtherSamples class](./src/test/kotlin/org/jetbrains/kotlinx/dataframe/samples/api/OtherSamples.kt). Generated
+HTML files will be stored in [docs/StardustDocs/snippets/manual](../docs/StardustDocs/snippets/manual).
+
+### KDoc Preprocesor
+
+The code you're working on needs to be edited in [src](src), but the KDocs are processed by the
+[KDoc Preprocessor](https://github.com/Jolanrensen/docProcessorGradlePlugin) when the project is published (or the task
+is run manually). The generated sources with adjusted KDocs will be overwritten
+in [generated-sources](generated-sources).
+See the [KDoc Preprocessing Guide](../KDOC_PREPROCESSING.md) for more information.
+
+KDocs can also be exported to HTML, for them to be reused on the website.
+Elements annotated with `@ExportAsHtml` will have their generated content be copied over to
+[docs/StardustDocs/snippets/kdocs](../docs/StardustDocs/snippets/kdocs).