Fix AdminAuthorization implementation.

- execute() does the magic of getting privileges and starting
  the process
- hasAdminRights() simply returns if we started privileged..

Change-Id: I0940a02556fe240af0ee7dfb068f7f8009eb683e
Reviewed-by: Karsten Heimrich <karsten.heimrich@digia.com>
Enable C++11 mode in compilers

Qt 5 uses C++11 features mostly for speeding up things.

Change-Id: Idcb3a95cd24b44c5147ff2e14f468f069da5e0c3
Reviewed-by: Niels Weber <niels.weber@digia.com>
Reviewed-by: Karsten Heimrich <karsten.heimrich@digia.com>
Enable QStringBuilder

QStringBuilder improves the speed of string concatenation a lot ...

Change-Id: I9dedf7c3335ebf4a9194e837f9eb8135fae11356
Reviewed-by: Karsten Heimrich <karsten.heimrich@digia.com>
Replace auto_ptr

auto_ptr is deprecated in C++11. Use QScopedPointer instead.

Change-Id: I63fd4de0a6edb329046ed9433e295407d95a9f95
Reviewed-by: Niels Weber <niels.weber@digia.com>
Reviewed-by: Karsten Heimrich <karsten.heimrich@digia.com>