debugging of undo and redo

undo and redo should be working for add and edit.
still working on delete
Further Debug of undo and redo

Delete is working. Require further testing. Able to undo deleteAll as
well. undo of add will now allow the task to go back to original
location
Slight refactoring

Move the copying of task into task.java
Debugging

Debug of redo delete
Debugging of storage

Solve the problem where the program cannot open if the user previously
store a task containing regex
add more cases in controller
Merge branch 'master' into logic

Conflicts:
	src/Controller.java
	src/Logic.java
	src/Task.java
Merge branch 'logic'