Add ping (#222)

* Add ping

* rework to have only a unique ping

Author: Wardormeur

lib/ping.js

@@ -0,0 +1,5 @@
+'use strict';
+var ping = function (args, done) {
+    done(null, {status: 'ok'});
+};
+module.exports = ping;

users.js

@@ -15,6 +15,7 @@ module.exports = function (options) {
   var protocol = process.env.PROTOCOL || 'http';
   var requiredProfileFields = ['name', 'dob', 'country', 'place'];
 
+  seneca.add({role: plugin, cmd: 'ping'}, require('./lib/ping'));
   seneca.add({role: plugin, cmd: 'create_reset'}, cmd_create_reset);
   seneca.add({role: plugin, cmd: 'load'}, cmd_load);
   seneca.add({role: plugin, cmd: 'list'}, cmd_list);