revised install procedure
support Renren
Aadd Renren permissions.

   * http://wiki.dev.renren.com/wiki/%E6%9D%83%E9%99%90%E5%88%97%E8%A1%A8
Change to a better icon of renren:

   * http://a.xnimg.cn/favicon-rr.ico?ver=3
add TencentWeibo
add SinaWeibo
Merge branches 'readme-upgrade', 'cn-micro-blogs-only' and 'renren'