Added comments to display handler.
Merge branch 'master' of https://github.com/cs2103aug2014-T13-2J/main

# By mervynwee
# Via mervynwee
* 'master' of https://github.com/cs2103aug2014-T13-2J/main:
  Add comments

Conflicts:
	src/main/logic/DisplayHandler.java