improve Vector<> with types that can be trivially moved and remove some unused code.

This optimization applies to sp<> and wp<> which should now perform about the same as regular pointers when placed in to Vector<>.
diff --git a/include/utils/Vector.h b/include/utils/Vector.h
index be365d8..ad59fd6 100644
--- a/include/utils/Vector.h
+++ b/include/utils/Vector.h
@@ -175,8 +175,7 @@
     : VectorImpl(sizeof(TYPE),
                 ((traits<TYPE>::has_trivial_ctor   ? HAS_TRIVIAL_CTOR   : 0)
                 |(traits<TYPE>::has_trivial_dtor   ? HAS_TRIVIAL_DTOR   : 0)
-                |(traits<TYPE>::has_trivial_copy   ? HAS_TRIVIAL_COPY   : 0)
-                |(traits<TYPE>::has_trivial_assign ? HAS_TRIVIAL_ASSIGN : 0))
+                |(traits<TYPE>::has_trivial_copy   ? HAS_TRIVIAL_COPY   : 0))
                 )
 {
 }