Improving Database and models

Description: Adding Checkin and Workday model classes to the project. They will help on handling data operations after getting them from database.
The DatabaseManager class was improved with methods for insert and select checkins and workday in a simple way.

Commit: Add

TaskNumber:#2
Creating Test Project

Description: Adding Test Project to hierarchy under test folder.
Initialy, tests for insert and select sql queries are already done.

Commit:Add

TaskNumber: #2