JetDiagnosticsTest migrated to TestGenerator

- test data files renamed from *.jet to *.kt

compiler/testData/diagnostics/tests/jdk-annotations/ArrayListClone.kt

@@ -0,0 +1,8 @@
+package kotlin1
+
+import java.util.*
+
+fun main(args : Array<String>) {
+    val al : ArrayList<Int> = ArrayList<Int>()
+    al.clone() : Any // A type mismatch on this line means that jdk-annotations were not loaded
+}