[FE 1.0] Introduce "range until operator" language feature, and report errors on its usages till 1.8

compiler/testData/diagnostics/tests/operatorsOverloading/until/customDefault.kt

@@ -0,0 +1,9 @@
+class A {
+    operator fun rangeUntil(other: A): Iterable<A> = TODO()
+}
+
+fun main(n: A, f: A) {
+    for (i in f<!UNSUPPORTED_FEATURE("The feature "range until operator" is only available since language version 1.8")!>..<<!>n) {
+
+    }
+}