Post-commit review for the new accessibility classes

[Frank Reininghaus]

Hi Amandeep and Frederik,

I started to go through the new code, fixed a couple of coding style
issues and removed some unnecessary complexity. The old version of
KItemListAccessibleCell::navigate() was the most complicated way to
return -1 I've ever seen ;-)

I'm by no means done, but I already have a few things that I'd like
you to take care of/comment on:

1. Your new files have no license header. This is totally unacceptable
and must be fixed ASAP.

2. You've wrapped most of the code in #ifndef QT_NO_ACCESSIBILITY, but
not the #includes for the QAccessible headers. I wonder if these
headers are actually installed if Qt is built without accessibility or
if someone who built a non-accessible Qt will get a build error here?

3. I see that you print some debug output in
KItemListViewAccessible::cellAt(). Is this still important for your
current debugging needs? If not, I'd prefer if this was removed.

Best regards,
Frank