Readonly form fields and their CSS styles

Inspired by: https://groups.google.com/forum/?fromgroups=#!topic/atk4/CC0b3YbDFkk

1) Fix outlining of readonly form fields.
2) Now because readonly fields will have their specific css class, you'll be able to address it in your custom CSS file.
3) As side-effect - in included CSS files tabs was converted to spaces to normalize source code indentation.