add recover minute feature for alert policy
add recover minute feature's document
amend alert view page
fix capacity page's js bug
Merge branch 'master' of https://github.com/dianping/cat
add alert http api
add alert interface's document
add intro infos to rule config page
Merge pull request #604 from leonindy/master

add recover minute feature for alert policy, amend alert view page, add alert http api, add intro infos to rule config page