Update README.md

Provided basic product description, support commands and expected
output format.
Merge branch 'interface'
Fix javadoc in Logic.java
Remove unnecessary try/catch block in Logic.viewTask
Remove unnecessary imports in DatePair, Logic and Task
Clean up LogicTest
Merge branch 'quality_control'
Integrate JournalController to Logic to support undo/redo.

There is no working version of Delete action so was not added.
Add command distribution to undo/redo in Logic.executeCommand

Now undo/redo should work
Merge branch 'journal'
Merge branch 'master' of https://github.com/cs2103aug2014-w11-4j/main

Fix Conflict