TestRunner support in test's build.gradle

* Fixes to tests
 * RunKonanTest runs tests build with TestRunner
 * Standalone tests

backend.native/tests/mangling/mangling.kt

@@ -1,7 +1,3 @@
-package mangling.mangling
-
-import kotlin.test.*
-
 fun test_direct() {
     val mutListInt = mutableListOf<Int>(1, 2, 3, 4)
     val mutListNum = mutableListOf<Number>(9, 10, 11, 12)
@@ -32,7 +28,7 @@ fun test_multiple_constructors() {
     mangle3(number)
 }
 
-@Test fun runTest() {
+fun main(args: Array<String>) {
     test_direct()
     test_param()
     test_multiple_constructors()

backend.native/tests/mangling/manglinglib.kt

@@ -1,5 +1,3 @@
-package mangling.mangling
-
 public fun mangle1(l: List<Int>) {
     println("Int direct $l")
 }