Issues template added and update to `README.md`

[LotharukpongJS]

According to ChatGPT, issues templates in GitHub can help with:

Consistency: An issues template ensures consistency across bug reports, feature requests, and other types of project-related issues. By providing a predefined structure, it helps contributors provide the necessary information in a consistent format, making it easier for maintainers to understand and address the problems.

Relevant information: The template prompts users to include essential details when reporting an issue. This can include steps to reproduce the problem, expected behavior, actual behavior, operating system or environment details, and any relevant logs or error messages. Having this information readily available saves time and provides a clearer context for issue resolution.

Efficient issue triaging: When multiple issues are reported, maintainers need to prioritize and allocate resources accordingly. An issues template can include fields like severity, priority, or tags, allowing contributors to categorize and label their issues appropriately. This helps maintainers quickly identify critical or high-priority problems and organize their work effectively.

Reduced back-and-forth communication: By providing specific sections for relevant information, an issues template reduces the need for maintainers to ask clarifying questions or request additional details. This can save time and streamline the issue resolution process, especially for projects with large contributor communities or numerous bug reports.

Improved collaboration: Issues templates can also foster better collaboration by providing guidelines for potential contributors. It helps new users understand what information is expected, how to format their contributions, and how to engage with the project effectively. This lowers the barrier to entry for new contributors and encourages participation.

Documentation and historical record: By using an issues template, each reported issue becomes a standardized record of problems, discussions, and resolutions. This serves as valuable documentation, enabling future contributors and maintainers to understand past issues and their resolutions. It also helps identify recurring patterns or common problems that need to be addressed.

While not all applicable here, I suggest four issues templates to improve some of these points. I also suggest a change to the README.md so that users can be directed to precomputed phylomaps.

[HajkD]

Absolutely brilliant!