Returned string message
Wrote new code for redo
Returned null for Repeat's undo
Wrote code for undo
Added command to undo to undo stack, removed switch cases
Merge branch 'master' of https://github.com/cs2103aug2014-t7-2/main

# By Natalie Rawle
# Via Natalie Rawle
* 'master' of https://github.com/cs2103aug2014-t7-2/main:
  added faux fixes for undo in redo and repeat

Conflicts:
	dataManipulation/Redo.java
	dataManipulation/Repeat.java