add log4j2
update log and log for search
resolve conflicts
Merge pull request #133 from cs2103aug2014-t17-1j/Jack_UI

Jack ui
resolve classpath conflict
Merge branch 'master' of github.com:cs2103aug2014-t17-1j/main
Stop tracing for log
Delete print statement
Clean up storage list and readwrite json file
Edit for help panel
Some unused constants are removed