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/basic/common/NoNestedClassesFromImplicitQualifier.kt

@@ -0,0 +1,11 @@
+class Outer {
+    class Nested
+    inner class Inner
+}
+
+fun Outer.foo() {
+    <caret>
+}
+
+// ABSENT: Nested
+// EXIST: { itemText: "Inner", tailText: "()", typeText: "Outer.Inner" }