backend/tests: Add blackbox tests from Kotlin JVM

Added tests from testData/codegen/box directory. There are blackbox tests
in other directories and they are to be added.

backend.native/tests/external/codegen/blackbox/closures/localGenericFun.kt

@@ -0,0 +1,12 @@
+fun box() : String {
+
+    fun <T> local(s : T) : T {
+        return s;
+    }
+
+    if (local(10) != 10) return "fail1"
+
+    if (local("11") != "11") return "fail2"
+
+    return "OK"
+}