feat: gradle support (#10)

Switching to the ScaffoldIt Gradle Plugin adding:
- HytaleServer.jar via the official Hytale maven
- Monorepo support via `common {}` block
- Kotlin support via `useKotlin()` function
- Hot-reloading using DCEVM JVM and IDEA
- Automatic manifest in-place generation
- Automatic source path scaffolding
- Source-linked Devserver for zero jar
- Source-linked Asset Editor

settings.gradle.kts

@@ -0,0 +1,17 @@
+rootProject.name = "dev.hytalemodding"
+
+plugins {
+    // See documentation on https://scaffoldit.dev
+    id("dev.scaffoldit") version "0.2.1"
+}
+
+//
+// Automatically configures the builds, but you can switch scripts if you wish!
+//
+hytale {
+    manifest {
+        Group = "HytaleModding"
+        Name = "ExamplePlugin"
+        Main = "dev.hytalemodding.ExamplePlugin"
+    }
+}