add permissions plugin

plugins/permissions.js

@@ -0,0 +1,36 @@
+var startDate;
+
+module.exports = {
+
+    id: 'permissions',
+    defaultConfig: {
+        allowedUserNames: [],
+        message: '⛔ you are not authorized'
+    },
+
+    plugin(bot, pluginConfig) {
+
+        bot.mod('message', (data) => {
+            const userId = data.message.from.id;
+            if (pluginConfig.allowedUserNames.indexOf(data.message.from.username) < 0) {
+                data.message = {};
+                bot.sendMessage(userId, pluginConfig.message);
+            }
+
+            return data;
+        });
+
+        bot.on('start', () => {
+            startDate = Date.now();
+        });
+
+        bot.mod('message', (data) => {
+        if (data.message.date*1000 < startDate) {
+            data.message = {};
+        }
+
+        return data;
+    });
+
+    }
+};