Some refactoring for workset.
Initial commit for workset gui.
Implement logic to sort the worksheets in a workset by inserting order instead of sorted by worksheetId. Bug fixing.
Add aware interface for authors; Fix bugs.
Add aware interface for created time.
Add aware interface for last updated time.
Refactor java docs in class headers.
Refactor worksheet GUI, mask worksheet id.
Add created time and last updated time to worksheet.
Add comment field to worksheet. Modify DAO for worksheet.
Add aware interface for comment.
Fix toString for documents.
Rename some methods in DAO.
Remove some temporary data in home objects. Fix bug of create/edit note.
Hide worksheetId from UI.
Add note status field to UI.
Add menu to worksheet note status; Assign different color for each status.
Fix the bug that chapter/worksheet is not shown correctly when panel is resized.