Project version 1, 2, 3 and 4 completed by Hanbin Lee
[Description]
This program has 4 different versions. Additional features is added as version number goes up.
In:
Version 1, the program displays all the records of the .csv file.
Version 2, the program provides CRUD, refresh and reading single or multiple data option.
Version 3, reading single or multiple data option is removed and now the program uses thread for each operation.
Version 4, 2 new options' added: Sorting the result before display and writing to a new text file.
*Unit testing that adds new data working correctly.