Move compiler scripting tests to scripting plugin, remove unused funs

also remove some tests that are covered in the scripting-compiler
tests now.
Part of the cleanup to rewrite scripting to the new infrastructure.

plugins/scripting/scripting-compiler/testData/compiler/fib_dsl.kts

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