suppress deprecation warnings from nan
suppress deprecation warnings from nan

* while waiting for https://github.com/nodejs/nan/pull/811

royaltm/node-murmurhash-native,royaltm/node-murmurhash-native,royaltm/node-murmurhash-native,royaltm/node-murmurhash-native,royaltm/node-murmurhash-native,royaltm/node-murmurhash-native