Fix is_featured, creation_date

Hi! I've added some fixes to your great blog module:

- Added is_featured in the category view.
- Added simple style to highlight featured posts.
- Added icon-asterisk to featured posts.
- Added creation_date to the post's info in category main view.
- Hiding info of Categories if the value is 'uncategories'.
- Passing is_featured, viewed and smartshowviewed values to the view in main post view.
- Little fix in default text.
- Fix: Hiding 'Posted by' in category_loop.php when 'Show Author Name' is disabled.