Tidied up Game Dev Tools and added new sections.

Changes:

Redirect/storage links that need adding/fixing:

"Learn Game Development" under Game Dev Tools.
Storage links under Game Engines.
"Pre-made Assets" under Asset Creation.
Organized links into new subsections and added tags.
Included redirect for cybersecurity learning resources.
Added a handful of new links.
New Stars:
- "Learn Gamedev", "MagicTools" - popular and well-maintained awesome lists featuring tons of guides and learning resources for game devs.
- "develop.games" - starred by frisk, has useful game dev resources and great guides.
- "Brackeys" - YT channel suggested by frisk.
Removals:
- GitHub game engines collection - replaced with better link suggested by frisk.
- "Awesome Gamedev" - replaced with new up to date resources.
- "UnrealEnginePython" - no updates in 4 years, project has been put on hold + tons of unsolved issues.
- "UnrealCLR" - no longer maintained, not sure how useful it is.
- "Vanguard" - removed by meinai_raito: "dead, last commit was 2 years ago, 28 stars, no build and require unity editor to run".