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/smart/this/QualifiedThisOfExtensionLambda3.kt

@@ -0,0 +1,12 @@
+fun<T> accept1(handler: String.(t: T) -> Unit){}
+fun accept2(handler: Int.() -> Unit){}
+
+fun foo(){
+    accept1<String>({
+                        accept2({
+                                    val s: String = <caret>
+                                })
+                    })
+}
+
+// EXIST: this@accept1