'quick' directory renamed to 'tests' which reflects its contents

compiler/testData/diagnostics/tests/ClassObjectCannotAccessClassFields.jet

@@ -0,0 +1,9 @@
+// http://youtrack.jetbrains.net/issue/KT-20
+
+class A() {
+    val x = 1
+
+    class object {
+        val y = <!UNRESOLVED_REFERENCE!>x<!>
+    }
+}