Alpha version released

Alpha version was just released. It adds some new features and enhances its functions.

The following is the change logs.

1. Add "Add Current Url" to the context menu of TreeView.

2. Add 'Favorite' menu.

3. Add 'Open Rss Site' menu.

4. Use uniform date format for sorting of multiple groups.

5. Add commentRss to update item process.

6. Enhance RSS parsing and comments handling.

7. Fix update period calculation bug.

8. Add context menu on CoolBar for convenience.

9. Add MouseDown event to the Text widget to select all text when it gets focus.