[Hangouts] Add interactive cards support

examples/google_hangouts_bot.js

@@ -89,3 +89,7 @@ controller.hears('cards', 'message_received', function (bot, message) {
         }
     });
 });
+
+controller.on('card_clicked', function (bot, message) {
+    bot.reply(message, 'This is a card click');
+});

lib/GoogleHangoutsBot.js

@@ -207,6 +207,10 @@ function GoogleHangoutsBot(configuration) {
             message.type = 'ROOM' === message.space.type ? 'bot_room_leave' : 'bot_dm_leave';
         }
 
+        if ('CARD_CLICKED' === message.type) {
+            message.type = message.type.toLowerCase();
+        }
+
         next();
 
     });