Add Kotlin Buildscripts + Add Kotlin Buildscript Support to Testing + Update Gradle Plugins, Gradle and MinecraftForge

[Codetoil]

Lex mentioned that the Kotlin Buildscript needed to be added to the testing framework. I went ahead and did that.
While I was there, I bumped the Gradle Plugins, Gradle and MinecraftForge, since they should probably be up to date.

[LexManos]

This doesnt actually seem to add any kotlin examples
Nore does it seem to of actually run the _internal updates.
What is the goal of this PR?

[Codetoil]

It adds the existing kotlin buildscript into the _internal testing framework. Plus I made some modifications to it to extend its capabilities.

[Codetoil]

If you want me to add the kotlin examples in the same PR, I could, but that'll take me some time to make.

[LexManos]

Worth doing yes, and like I said, the updateBuilds task doesnt seem to of been run because the current projects output a range, which is not what the code does.
Jonathan changed things to a range after I wrote that task and never updated it.

[Codetoil]

I did actually run it though. I modified the task to output a range since that what I thought you wanted.

[LexManos]

Oh my bad, forgot it was hardcoded, thought I had it pick from that subproject's version. Im an idiot.
I'll try and remember to look at this tomarrow. But yes, having a kotlin version of each example is the overall goal.