New report class, jsp and servlets.

All documentation and comments will be added soon.
1. New report class (ReportGenerator), that handles all report logic.
Will be modified for all report functionality.
2. Added servlets ReportTestServlet, that will be re-worked and modify
to handle request related with report creation and view, and
DownloadReportServlet that will work with requests related with report
downloading.
3. Added report.jsp to display requested report as html.
4. Added a button to admin page to view report. UI must be modified to
allow user select a report type and set date period.
5. Deleted unused class.