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/InsertVoidJavaMethod.kt

@@ -0,0 +1,7 @@
+import java.io.File
+
+fun test() {
+  val f = File("testFile")
+  // Should be no ;
+  f.deleteOnExit<caret>
+}