Enable padding as a grouped property

We want padding to be a grouped property as the
existing Margins property looks rather odd and
insconsistent.

Change-Id: I9e614f9161aaf01af200b19a1fb46a51beec6fb4
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>
Fix tab overlap on Windows XP and Windows Vista

In Windows XP style, we actually use different values
based on tab position. That means we have to pass these
values through the tab style option.

Change-Id: I65904a9a57326003cfddef1a12ada5dda2fa2eab
Reviewed-by: J-P Nurmi <jpnurmi@digia.com>
Testbench: Add properties

- checkedState
- partiallyCheckedEnabled
- alternatingRowColors

And update status bar.

Change-Id: I837aac4788e04901418264374c84ae92c2234b2f
Reviewed-by: Jens Bache-Wiig <jens.bache-wiig@digia.com>