TaskAdder() now functional. Takes in the List<CommandComponents> that is passed in from CommandHandler() and returns a task if successfully added, throws an exception if it fails to do so (i.e. If a duplicate task is found within)
Merge branch 'master' of https://github.com/cs2103aug2014-t7-2/main

# By Yui Wei (2) and Natalie Rawle (1)
# Via Yui Wei
* 'master' of https://github.com/cs2103aug2014-t7-2/main:
  corrected the skeleton code in exactmatchsearcher.
  added getAddMessage, getDeleteMessage and getEditMessage skeleton code in ezCMessages. modified CommandHandler to return the message String
  Example for Yui of ezCMessage interface. Will change implementation later.
Created a new EditedPair object for two Task objects: one BEFORE editing and one AFTER editing. This is for display purposes for the user.
TaskEditor() method has been completed, less the ability to edit the completion status of a task. Requires Nat to edit the CommandComponents() method to include that as a CommandComponent type. TaskEditor() method throws errors if a task that is to be edited cannot be found or, if after editing, creates an exact duplicate.
Added in a method to determine if a task exists in the list, require Kash to followup on the actual write-up of the code. This task is needed for the TaskEditor() method.