✨ Convert build scripts to Kotlin

Also added some new tasks to only build/install to maven local certain platforms
`buildMinecraft`, `installMinecraft`, `buildDiscord`, `installDiscord`, `buildIRC`, `installIRC`

buildSrc/build.gradle.kts

@@ -0,0 +1,7 @@
+plugins {
+    `kotlin-dsl`
+}
+
+repositories {
+    jcenter()
+}

buildSrc/src/main/kotlin/DependencyVersions.kt

@@ -0,0 +1,29 @@
+val versions = mapOf(
+        "checker-qual" to "3.8.0",
+        "geantyref" to "1.3.11",
+        "errorprone" to "2.4.0",
+        "errorprone_javac" to "9+181-r4173-1",
+        // DISCORD DEPENDENCIES
+        "javacord" to "3.1.1",
+        "jda" to "4.2.0_209",
+        // MINECRAFT DEPENDENCIES
+        "brigadier" to "1.0.17",
+        "bukkit" to "1.13.2-R0.1-SNAPSHOT",
+        "commodore" to "1.9",
+        "bungeecord" to "1.8-SNAPSHOT",
+        "cloudburst" to "1.0.0-SNAPSHOT",
+        "adventure-api" to "4.3.0",
+        "adventure-platform" to "4.0.0-SNAPSHOT",
+        "paper-api" to "1.15.2-R0.1-SNAPSHOT",
+        "velocity-api" to "1.1.0",
+        "jb-annotations" to "20.1.0",
+        "guava" to "21.0-jre",
+        // IRC DEPENDENCIES
+        "pircbotx" to "83a4c22e80",
+        // TEST DEPENDENCIES
+        "jupiter-engine" to "5.7.0",
+        "jhm" to "1.25.2"
+)
+
+val vers
+    get() = versions

buildSrc/src/main/kotlin/GroupedBuild.kt

@@ -0,0 +1,24 @@
+import org.gradle.api.Project
+import org.gradle.kotlin.dsl.invoke
+
+fun Project.buildGroups(vararg groupNames: String) =
+        groupNames.forEach(this::buildGroup)
+
+fun Project.buildGroup(groupName: String) {
+    tasks {
+        register("build$groupName") {
+            group = "cloud"
+            rootProject.subprojects
+                    .filter { it.projectDir.parentFile.name == "cloud-${groupName.toLowerCase()}" }
+                    .map { it.tasks.getByName("build") }
+                    .forEach { dependsOn(it) }
+        }
+        register("install$groupName") {
+            group = "cloud"
+            rootProject.subprojects
+                    .filter { it.projectDir.parentFile.name == "cloud-${groupName.toLowerCase()}" }
+                    .map { it.tasks.getByName("publishToMavenLocal") }
+                    .forEach { dependsOn(it) }
+        }
+    }
+}