chore: add issue templates

[zivkovicmilos]

Description

This PR adds 2 issue templates to the repo, for easier issue management:

1. Simple issue template with a basic description
2. Detailed issue template with questions the user is supposed to answer

The issue templates can be chosen when creating a new issue.

Changes include

• Bugfix (non-breaking change that solves an issue)
• Hotfix (change that solves an urgent issue, and requires immediate attention)
• New feature (non-breaking change that adds functionality)
• Breaking change (change that is not backwards-compatible and/or changes current functionality)

Checklist (for contributors)

• I have assigned this PR to myself
• I have added at least 1 reviewer
• I have added the relevant labels
• I have updated the official documentation
• I have added sufficient documentation in code

Testing

• I have tested this code with the official test suite
• I have tested this code manually

Additional comments

cc @piux2 @anarcher