Look and feel

- File paths contain a space after each slash to allow HTML to wrap long text in the table cells.
- Source code is displayed inside <pre> element so there is no need to replace spaces by &nbsp;.
- Widths of the table columns updated.
- Tested in Chrome, Opera, Firefox, Konqueror and IE 11.
Code refactoring and clean up

- TodosComment.text renamed to sourceCode.
Clean up of data model

- The data are stored in a new format that is not backward compatible.
- TodosPatternStatistics class created as a high level unmodifiable class (moved from TodosReportStatistics).
- TodosReport is able to compute and return the statistics (moved from TodosReportStatistics).
- Many unused methods removed from TodosReport.
- TodosReport should not be seriable.
- Methods renamed to use bettern names.
- Javadoc comments added.