fixed edge_descriptor stability problem for case of EdgeList=vecS by

changing stored_edge_property to hold the properties object by auto_ptr
instead of by value


[SVN r8487]

libs/graph

@@ -1 +1 @@
-Subproject commit 2d5fcd13e30b105de04cc791f2ca007ade6860a6
+Subproject commit fd7f5d5a0eb7d01bf1e53f6838dcf5b082a3458d