add author attribution

ggjspencer · tcalmant · commit 31d3ae43761a · 2018-01-17T18:32:41.000+01:00
diff --git a/AUTHORS b/AUTHORS
@@ -8,3 +8,4 @@ Many thanks to the contributors:
 * Patrick J. McNerthney (@iciclespider)
 * @voetsjoeba
 * Vadim Markovtsev (@vmarkovtsev)
+* Jason Spencer, Google LLC (@j8spencer)
