UI back to the state of receiving String to display, a better version of UI is on the way!!!
the following changes: 1. display window is not directly editable now; 2. the window is not resizable; 3. tried to add in a logo but it doesn't show....
logo added
Merge branch 'master' of https://github.com/cs2103aug2014-w15-3J/main
new UI layout, accept strings to display