add web ui for :
1. viewing log file
2. get/set log4j log level online
limit strickly on tail log file bytes
Merge branch 'master' of https://github.com/nathanmarz/storm into issuse-543
mv log viewer from supervisor process to a seperated daemon
Merge branch 'master' into xiaokang-issuse-543
remove UI template from log because it doesn't link to right place, remove 'log' from port display