Reviewed-by: Friedemann Kleint

By only providing a qtInstallDir variant

This splits up the edit and active settings. Let people try it and
report usability problems. I'm not 100% convinced of the layout either.

Reviewed-by: TrustMe

Rationale: The concept of a "Qt Dir" is dead ever since Qt can be
installed. Specifying the qmake location otoh makes it possible to
unambigously detect all parts of a Qt installation.

Also makes the code a lot smaller.

Closer again to qmake, ossi won't like it, but this is exactly what
qmake does, even it it looks a little bit strange. He can come up with
a better fix after he is back from vacation.

Previously, the image used as background forced it to be white, which
made the text impossible to read when the palette foreground color
happened to be white as well.

Task-number: 258167

	modified:   src/plugins/qt4projectmanager/qtmodulesinfo.cpp

Since we can easily do that, just do it. No gurantee that we aren't
going to use rtti in the future.

Reviewed-by: dt

Let's not irritate MSVC

Also adding category folders for the different file types
(source files, header files, resource files, form files, other files).