V0.5 Duke Personal Assistant

Improved exception handling over previous version

V0.3 Fixed deletion bug

Merge pull request #2 from jerroldlam/branch-Level-9

add find keyword function

V0.2 Support statistics from loaded list

Support loading statistics from loaded list

V0.1 of the Duke Personal Assistant

Duke has the ability to keep a task list of 3 different task types, namely ToDo, Deadline and Events. It can also load and save the task list as a text file.