refactor, moved files and folders, improved test cases

Signed-off-by: Nicholas Lum <nicholaslum444@hotmail.com>
Merge branch 'develop' of https://github.com/cs2103aug2014-t16-3j/main into develop

Conflicts:
	src/udo/tests/UItest.java
	src/udo/ui/util/ToDoScreen.java
	src/udo/ui/util/uDoPopup.java