Avoid using reflected types in the scripting API

since it causes numerous classloading issues. Using the wrapping types
and reload them in the proper context when needed.
Note: this version supports only classes, but the wrapping type could
be extended to support other types in the future.
+ numerous fixes related to proper loading and handling of the templates.

libraries/tools/kotlin-gradle-plugin/build.gradle

@@ -65,7 +65,6 @@ dependencies {
     runtime project(':kotlin-reflect')
     runtime project(':kotlin-scripting-common')
     runtime project(':kotlin-scripting-compiler')
-    runtime project(':kotlin-scripting-jvm')
     runtime project(path: ':kotlin-scripting-gradle', configuration: 'runtimeJar')
 
     // com.android.tools.build:gradle has ~50 unneeded transitive dependencies

libraries/tools/kotlin-maven-plugin/src/main/java/org/jetbrains/kotlin/maven/ExecuteKotlinScriptMojo.java

@@ -185,7 +185,7 @@ public class ExecuteKotlinScriptMojo extends AbstractMojo {
             configuration.put(CommonConfigurationKeys.MODULE_NAME, JvmAbi.DEFAULT_MODULE_NAME);
 
             ScriptingCompilerConfigurationExtensionKt.configureScriptDefinitions(
-                    scriptTemplates, configuration, messageCollector, new HashMap<>()
+                    scriptTemplates, configuration, this.getClass().getClassLoader(), messageCollector, new HashMap<>()
             );
 
             KotlinCoreEnvironment environment = KotlinCoreEnvironment.createForProduction(rootDisposable, configuration, EnvironmentConfigFiles.JVM_CONFIG_FILES);