MPP: Attach all classes/resources directories to the runtime classpath (KT-30710)

idea/testData/gradle/newMultiplatformImport/runtimeClasspath/build.gradle

@@ -0,0 +1,25 @@
+buildscript {
+    repositories {
+        mavenCentral()
+        maven { url 'https://dl.bintray.com/kotlin/kotlin-eap' }
+    }
+
+    dependencies {
+        apply from: "include.gradle"
+        def kotlinVersion = gradleKotlinPluginVersion('1.3.40-eap-67')
+        classpath("org.jetbrains.kotlin:kotlin-gradle-plugin:$kotlinVersion")
+    }
+}
+
+apply plugin: 'kotlin-multiplatform'
+apply plugin: 'kotlin-kapt'
+
+
+repositories {
+    mavenCentral()
+    maven { url 'https://dl.bintray.com/kotlin/kotlin-dev' }
+}
+
+kotlin {
+    jvm('jvm') { withJava() }
+}