Update graphmetrics version (#132)

James Wallis · sjanuary · commit abd7659ed308 · 2017-12-11T14:14:35.000Z
diff --git a/public/graphmetrics b/public/graphmetrics
@@ -1 +1 @@
-Subproject commit 6f009cf75111a6292fe78835e571aa8009b72ee6
+Subproject commit b397417320ba48c6dccc49a8c3891ab5e61da1be
