Enhanced README Documentation

[Vikranth3140]

This PR addresses #4 to enhance the README documentation for the Notipyer project. It follows markdown-embed-code-from-file as mentioned in #4 issue.

The improvements include:

• Added badges for the PyPI version and license.
• Improved structure and clarity.
• Detailed installation instructions.
• Clear configuration and usage examples for email and Slack notifications.
• Added sections for contributing, license, and contact information.

These changes aim to provide a better user experience and make it easier for new users to get started with Notipyer.