THRIFT-3086 add valgrind suppression support to the ExperimentalMemCheck test run

Patch: James E. King, III

This closes #481
diff --git a/test/valgrind.suppress b/test/valgrind.suppress
new file mode 100644
index 0000000..41f9414
--- /dev/null
+++ b/test/valgrind.suppress
@@ -0,0 +1,9 @@
+{
+   boost/get_once_per_thread_epoch/ignore
+   Memcheck:Leak
+   match-leak-kinds: reachable
+   fun:malloc
+   fun:_ZN5boost6detail25get_once_per_thread_epochEv
+}
+
+