modify the system page
add agent
clean before code
Merge pull request #332 from youyong205/master

refactor alert
修改系统监控展示层为最小化收取数据模型
resolve conflicts
modify system monitor nag order
Merge pull request #333 from youyong205/master

refactor code
使datetimepicker更友好化，加入了自动判断开始结束时间先后顺序
Merge branch 'master' of https://github.com/dianping/cat
解决冲突
本地处理历史report与model端处理当前report方式保持一致
Merge pull request #334 from jialinsun/master

加入system Agent、system page、修改系统监控展示层为最小化收取数据模型等
modify the code