chore: Add basic README (#62)

## What's Changed

This is based on https://github.com/apache/arrow-js/blob/main/README.md
.

Closes #23.

---------

Co-authored-by: Raúl Cumplido <[email protected]>

Author: kou

README.md

@@ -0,0 +1,49 @@
+<!--
+  Licensed to the Apache Software Foundation (ASF) under one
+  or more contributor license agreements.  See the NOTICE file
+  distributed with this work for additional information
+  regarding copyright ownership.  The ASF licenses this file
+  to you under the Apache License, Version 2.0 (the
+  "License"); you may not use this file except in compliance
+  with the License.  You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing,
+  software distributed under the License is distributed on an
+  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+  KIND, either express or implied.  See the License for the
+  specific language governing permissions and limitations
+  under the License.
+-->
+
+# Apache Arrow Swift
+
+[Apache Arrow](https://arrow.apache.org/) is a universal columnar format and multi-language toolbox for fast data interchange and in-memory analytics. It contains a set of technologies that enable data systems to efficiently store, process, and move data.
+
+## Install
+
+TODO: We should update this after we register this package to Swift Package Index.
+
+## Getting Started
+
+TODO: We should refer auto generated documentation on Swift Package Index after we register this package to Swift Package Index.
+
+## Getting involved
+
+Even if you do not plan to contribute to Apache Arrow itself or Apache Arrow integrations in other projects, we'd be happy to have you involved:
+
+* [Join the mailing list](https://arrow.apache.org/community/#mailing-lists): Share your ideas and use cases for the project
+* Follow our activity on [GitHub Issues](https://github.com/apache/arrow-swift/issues)
+* Contribute code
+
+We prefer to receive contributions in the form of GitHub pull requests. Please send pull requests against the [github.com/apache/arrow-swift](https://github.com/apache/arrow-swift) repository.
+
+If you are looking for some ideas on what to contribute, check out the [GitHub
+Issues](https://github.com/apache/arrow-swift/issues) for the Apache Arrow Swift project. Comment on the issue, [GitHub Discussions](https://github.com/apache/arrow-swift/discussions) and/or contact [[email protected]](https://arrow.apache.org/community/#mailing-lists) with your questions and ideas.
+
+If you'd like to report a bug but don't have time to fix it, you can still post it on GitHub issues.
+
+## License
+
+[Apache 2.0](https://github.com/apache/arrow-swift/blob/main/LICENSE.txt)