Deprecate version field and preserve order of script providers in extension point

It's impossible to guess the order of the final list when there're
providers from different vendors as they might have different versioning systems.

com.intellij.openapi.extensions.LoadingOrder constants can be used by plugins authors to
resolve priority issues.

compiler/frontend/src/org/jetbrains/kotlin/script/scriptTemplateProviderExtensionPoint.kt

@@ -27,7 +27,11 @@ interface ScriptTemplatesProvider {
 
     // for resolving ambiguities
     val id: String
-    val version: Int
+
+    @Deprecated("Parameter isn't used for resolving priorities anymore. " +
+                "com.intellij.openapi.extensions.LoadingOrder constants can be used to order providers when registered from Intellij plugin.",
+                ReplaceWith("0"))
+    val version: Int get() = 0
 
     val isValid: Boolean
 
@@ -42,7 +46,8 @@ interface ScriptTemplatesProvider {
     val environment: Map<String, Any?>?
 
     companion object {
-        val EP_NAME = ExtensionPointName.create<ScriptTemplatesProvider>("org.jetbrains.kotlin.scriptTemplatesProvider")
+        val EP_NAME: ExtensionPointName<ScriptTemplatesProvider> =
+                ExtensionPointName.create<ScriptTemplatesProvider>("org.jetbrains.kotlin.scriptTemplatesProvider")
     }
 }
 
@@ -55,16 +60,13 @@ fun makeScriptDefsFromTemplatesProviderExtensions(project: Project,
 fun makeScriptDefsFromTemplatesProviders(providers: Iterable<ScriptTemplatesProvider>,
                                          errorsHandler: ((ScriptTemplatesProvider, Exception) -> Unit) = { ep, ex -> throw ex }
 ): List<KotlinScriptDefinitionFromAnnotatedTemplate> {
-    val idToVersion = hashMapOf<String, Int>()
-    return providers.filter { it.isValid }.sortedByDescending { it.version }.flatMap { provider ->
+    return providers.filter { it.isValid }.flatMap { provider ->
         try {
-            idToVersion.get(provider.id)?.let { ver -> errorsHandler(provider, RuntimeException("Conflicting scriptTemplatesProvider ${provider.id}, using one with version $ver")) }
             Logger.getInstance("makeScriptDefsFromTemplatesProviders")
                     .info("[kts] loading script definitions ${provider.templateClassNames} using cp: ${provider.dependenciesClasspath.joinToString(File.pathSeparator)}")
             val loader = URLClassLoader(provider.dependenciesClasspath.map { File(it).toURI().toURL() }.toTypedArray(), ScriptTemplatesProvider::class.java.classLoader)
             provider.templateClassNames.map {
                 val cl = loader.loadClass(it)
-                idToVersion.put(provider.id, provider.version)
                 KotlinScriptDefinitionFromAnnotatedTemplate(cl.kotlin, provider.resolver, provider.filePattern, provider.environment)
             }
         }
@@ -73,4 +75,4 @@ fun makeScriptDefsFromTemplatesProviders(providers: Iterable<ScriptTemplatesProv
             emptyList<KotlinScriptDefinitionFromAnnotatedTemplate>()
         }
     }
-}
+}