Add possibility to specify supertypes for script, with tests

compiler/testData/script/fib_dsl.kts

@@ -0,0 +1,14 @@
+
+import org.jetbrains.kotlin.scripts.*
+
+// this script expected parameter num : Int
+
+fun fib(n: Int): Int {
+    val v = fibCombine( { fib(it) }, n)
+    System.out.println("fib($n)=$v")
+    return v
+}
+
+System.out.println("num: $num")
+val result = fib(num)
+