Created module idea-test-framework and moved classes needed for idea tests there

Moved tests for completion and their test data into module idea-completion

idea/idea-completion/testData/handlers/smart/ForLoopRange2.kt.after

@@ -0,0 +1,13 @@
+trait X
+trait Y
+
+fun X.iterator(): Y
+fun Y.next(): Int
+fun Y.hasNext(): Boolean
+
+
+fun foo(x: X?) {
+    for (i in x!!)<caret>
+}
+
+// ELEMENT_TEXT: "!! x"