Add Cris Ewing and Carlos de La Guardia to the authors list

Both contributed to the MIT CCX pull request

AUTHORS

@@ -204,4 +204,6 @@ Matjaz Gregoric <mtyaka@gmail.com>
 Kyle Boots <indagation@gmail.com>
 John Espinosa <johncespinosa@gmail.com>
 Phil McGachey <phil_mcgachey@harvard.edu>
-Sri Harsha Pamu <kmitharsha@gmail.com>
\ No newline at end of file
+Sri Harsha Pamu <kmitharsha@gmail.com>
+Cris Ewing <cris@crisewing.com>
+Carlos de La Guardia <carlos@jazkarta.com>