Reviewed-by: dt

- Give the controls a tooltip listing file details (date)
- Make building a QtConcurrent task
- Make log window scroll to bottom and pop up on error
- Make the build code pass on error messages about copying the
  source files to the log file
- Clean up the building code string-wise, use QLatin1String and
  translate messages, cache the icons. Use a QSharedPointer for
  the QtVersions in the settings page since they are passed to
  the BuildTask, which may outlive the dialog.

This reverts commit debb3961.
Success cannot be properly detected.

- Give the controls a tooltip listing file details (date)
- Make building a QtConcurrent task
- Make log window scroll to bottom and pop up on error
- Make the build code pass on error messages about copying the
  source files to the log file
- Clean up the building code string-wise, use QLatin1String and
  translate messages, cache the icons

Bug was introduced when separating the version list into "Autodetected" and
"Manual" subtrees.

Not able to give it an additional passphrase yet, though.

QtVersion provides possible toolchains that can be used by the
Qt version, e.g. winscw, gcce and armv5 for symbian-abld.

In the Qt Options Dialog.

and use it for some options dialogs.

The class fixes QTreeWidget to resize all columns to contents, except one
stretching column. As opposed to standard QTreeWidget, all columns are
still interactively resizable.

Also, warn if no MSVC version could be detected even though the Qt
version was build with MSVC. This should make the tracing of problem
a bit easier. Before, we have hidden the GUI elements if only one
compiler version could be found. This looks inconsistent and causes
confusion.

After all I don't need all that stuff in the cmakeplugin, all i needed
is now bundled in debugginghelper.h/cpp

More accurate name.

QtOptionsPage now has its own page.