Change gradle build to Kotlin DSL (#86)

build.gradle.kts

@@ -0,0 +1,111 @@
+val projectVersion = "0.4.0"
+val projectName = "konform"
+val projectGroup = "io.konform"
+val projectDesc = "Konform: Portable validations for Kotlin"
+val projectHost = "github"
+val projectOrg = "konform-kt"
+val projectLicense = "MIT"
+val projectLicenseUrl = "http://opensource.org/licenses/MIT"
+val projectDevelNick = "nlochschmidt"
+val projectDevelName = "Niklas Lochschmidt"
+val projectInceptionYear = 2018
+
+plugins {
+    kotlin("multiplatform") version "1.7.10"
+    id("maven-publish")
+    id("signing")
+    id("io.github.gradle-nexus.publish-plugin") version "1.3.0"
+}
+
+repositories {
+    mavenCentral()
+}
+
+group = projectGroup
+version = projectVersion
+
+kotlin {
+    sourceSets.all {
+        languageSettings {
+            languageVersion = "1.5" // Change to 1.6 when switching to Kotlin 1.8
+            apiVersion = "1.5"      // Change to 1.6 when switching to Kotlin 1.8
+        }
+    }
+    jvm {
+        compilations.all {
+            kotlinOptions.jvmTarget = "1.8"
+        }
+        withJava()
+        testRuns["test"].executionTask.configure {
+            useJUnitPlatform()
+        }
+    }
+    js {
+        browser {}
+        nodejs {}
+    }
+    sourceSets {
+        val commonMain by getting {
+            dependencies {
+                compileOnly(kotlin("stdlib"))
+            }
+        }
+        val commonTest by getting {
+            dependencies {
+                implementation(kotlin("test"))
+            }
+        }
+        val jvmMain by getting {
+            dependencies {
+                compileOnly(kotlin("stdlib-jdk8"))
+            }
+        }
+    }
+}
+
+tasks.create<Jar>("stubJavadoc") {
+    archiveClassifier.set("javadoc")
+}
+
+afterEvaluate {
+    publishing {
+        publications {
+            create<MavenPublication>("mavenJava") {
+                from(components["java"])
+                artifact(tasks["stubJavadoc"])
+                pom {
+                    name.set(projectName)
+                    description.set(projectDesc)
+                    url.set("https://github.com/konform-kt/konform")
+                    licenses {
+                        license {
+                            name.set(projectLicense)
+                            url.set(projectLicenseUrl)
+                            distribution.set("repo")
+                        }
+                    }
+                    developers {
+                        developer {
+                            id.set(projectDevelNick)
+                            name.set(projectDevelName)
+                        }
+                    }
+                    scm {
+                        url.set("https://github.com/konform-kt/konform.git")
+                    }
+                }
+            }
+        }
+    }
+}
+
+signing {
+    useGpgCmd()
+    sign(publishing.publications)
+}
+
+nexusPublishing {
+    repositories {
+        sonatype()
+    }
+}

settings.gradle.kts

@@ -0,0 +1 @@
+rootProject.name = "konform"