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/extensions/NoDuplicatedMethodForSmartCast.kt

@@ -0,0 +1,18 @@
+trait A {
+    fun foo(): Int
+}
+
+trait B: A {
+    override fun foo(): Int
+    override fun foo1(): Int
+}
+
+fun g(a: A) {
+    if (a is B) {
+        a.fo<caret>
+    }
+}
+
+// EXIST: foo
+// EXIST: foo1
+// NUMBER: 2