Website overhaul

[SandeMC]

The guide is currently undergoing a full-on overhaul that'll touch on almost every page. The guide won't be updated until the overhaul is complete. You can see the progress below:

• [x] Introduction (double check the requirements later)
• [x] Discord Server (removed and merged to Introduction)
• [x] Donations (removed and merged to Credits)
• [x] Preparation (new page)
• [x] Drag-and-Drop Archive
• [x] Downgrading (separated into a category)
• [x] Optimization
• [x] Additional Setup
• [x] Essential Modding:
  • [x] FusionFix
  • [x] ZolikaPatch
  • [x] Various Fixes
  • [x] Additional Fixes (List) (new page)
• [x] Recommended Enhancements (new page)
• [x] Extras:
  • [x] Multiplayer
  • [x] Trainers
  • [x] Launcher
  • [x] OpenIV
  • [x] Modloading
  • [x] Mods
• [x] Resources (new category):
  • [x] Mod Dependencies
  • [x] Credits
  • [x] Troubleshooting
• [x] Navigation changes
• [x] Markdown rules compliance & better tweaks for the rules
• [x] Fix my irks with CONTRIBUTING.md
• [ ] Russian translation pass

Closes #11.

[henrygame3]

That is a big change