[MQTT over WebSocket(SSL)]() Now!

[Plugin Achitecture](https://github.com/emqtt/emqttd/wiki/Plugin%20Design) based on OTP application

[Trace MQTT Packets or Messages]() to log files

Feature: issue #40, #115 - WebSocket/SSL Support

Feature: issue #93 - Trace API Design

Improve: issue #109 - emqttd_broker should add subscribe, notify API

Improve: update README.md to add ‘Goals’, ‘Contributors’ chapters

Change: rename etc/app.config to etc/emqttd.config

Bugfix: critical issue #54 - error when resume session!

Bugfix: issue #118 - error report when UNSUBSCRIBE with no topics

Bugfix: issue #117 - sys_interval = 0 config cannot work

Bugfix: issue #112 - Makefile to support build plugins