Merge pull request #377 from leonindy/master

add system alert task and page
添加所有系统监控指标，重构Agent
clean code
重构graph creator代码
clean
clean

This reverts commit 6062990697636508cc849847d03999a0bdb5e94d.
rebuild components
Merge pull request #379 from jialinsun/master

添加所有系统监控指标，重构Agent,graph creator代码
change Triple to AlertEntity
rename AlertEntity to AlertResultEntity
重构agent代码
Merge pull request #380 from jialinsun/master

重构agent代码
add table alert
add mail title when storing alert infos
add store alert feature for ExceptionAlert
Merge branch 'master' of https://github.com/dianping/cat
change find rule logic: find productline first, then metric item
add find-rule result event when alert tasks are running