[feat] Added library block to UMC setup

[poizzy]

This PR adds the possibility to add libraries for UMC submods directly in the umc.json. Highly inspired by TeamOpenIndustry/UniversalModCore#204. Before this PR is mergeable, we need to enable the shade plugin in the build.gradle template, and add some aditional variable tags.

Usage:

"mod": {
    //...
    "libraries": [
        {
            "repository": "maven repositor like eg: https://repo1.maven.org/maven2/",
            "artifact": "groovy short form like: com.google.code.gson:gson:2.13.2"
            "path": "path to a jar file, alternative to repository + artifact"
            "type": "shade/implementation/runtime/(compile)"
            "relocate": "old.path | new.path"
            "onlyIn": ["1.12.2-forge", "1.17.1-forge"]
        }
    ]
}

[Goldenfield192]

We might have to deal with flatDir above 1.17 as files won't work on there anymore