Reorganize tests

Author: liufengyun

tests/init/pos/early-promote.scala renamed to tests/init/neg/early-promote.scala

@@ -24,7 +24,7 @@ class A { // checking A
     def c = new C
   }
   val b = new B()
-  List(b) // Direct promotion works here
+  List(b) // error: no promotion for objects that contain inner classes
   val af = 42
 }
 

tests/init/pos/features-doublelist.scala renamed to tests/init/neg/features-doublelist.scala

@@ -1,6 +1,6 @@
 class DoubleList {
   class Node(var prev: Node, var next: Node, data: Int)
-  object sentinel extends Node(sentinel, sentinel, 0)
+  object sentinel extends Node(sentinel, sentinel, 0)  // error // error
 
   def insert(x: Int) = ???
 }