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/whenEntry/8.kt

@@ -0,0 +1,12 @@
+import java.lang.annotation.ElementType
+
+fun foo(e: ElementType) {
+    when(e) {
+        ElementType.FIELD -> x()
+        <caret>
+    }
+}
+
+// ABSENT: FIELD
+// EXIST: TYPE
+// ABSENT: e