chore: add Open Collective sponsors badge to README (#34)

Adds the Open Collective sponsors badge so visitors can see and click
through to the Open Collective page.

Badge: `[![Open
Collective](https://img.shields.io/opencollective/all/codemind?label=sponsors)](https://opencollective.com/codemind)`

<!-- This is an auto-generated comment: release notes by coderabbit.ai
-->

## Summary by CodeRabbit

* **Documentation**
* Updated changelog with initial release notes and upcoming roadmap
items.
  * Added funding badge to project README.

* **Chores**
  * Added funding configuration file.

<!-- end of auto-generated comment: release notes by coderabbit.ai -->

---------

Co-authored-by: Vineeth Wilson <vineeth.wilson@siemens.com>

Author: vineethwilson15

README.md

@@ -10,6 +10,7 @@
 [![License: MIT](https://img.shields.io/badge/License-MIT-yellow.svg)](LICENSE)
 [![Python 3.9+](https://img.shields.io/badge/python-3.9+-blue.svg)](https://www.python.org/downloads/)
 [![PRs Welcome](https://img.shields.io/badge/PRs-welcome-brightgreen.svg)](CONTRIBUTING.md)
+[![Open Collective](https://img.shields.io/opencollective/all/codemind?label=sponsors)](https://opencollective.com/codemind)
 
 <br/>