Reverted old version of CSR graph for compatibility, with a #define to switch between the modes; cleaned up interface of new CSR graph; fixed tests and docs accordingly

[SVN r53655]

libs/graph

@@ -1 +1 @@
-Subproject commit 77b148e6db4cc79420f77a95d1b8d37e6274f537
+Subproject commit 43b99f3fbe0408ff31b20988c41386aab232b06e