modify the connect timeout
fix NPE
fix mail sender error and refactor code
fix bug
fix config error
fix paas system monitor bug & optimize
Merge branch 'master' of https://github.com/dianping/cat
Merge pull request #452 from youyong205/master

fix many bug
Merge pull request #453 from jialinsun/master

fix paas system monitor bug & optimize detail
resolve conflicts