[Docs] Troubleshooting

[liplum]

Provide users information and detailed guide on how to fix some issues, warnings and errors, that they might encounter.

[JojoFR1]

Possible issues we can help user through:

• Why is my input/output/recipe "empty"
• Why is it not finding my item/fluid/unit/block
• Injection struggle

If you think any other issue should be addressed please comment and let us know.