QPdfEngine - Remove Producer copyright notice

Remove the copyright notice from the PDF Producer field which could be
misunderstood. Comparison to other PDF Producers shows no other company
does this.

Based on https://codereview.qt-project.org/#change,70182

Task-number: QTBUG-33853
Change-Id: I3a2820c1466963e7391b4a9a729c7261a3582e0b
Reviewed-by: Jake Petroules <jake.petroules@petroules.com>
Reviewed-by: Lars Knoll <lars.knoll@digia.com>
Reviewed-by: John Layt <jlayt@kde.org>
Correct QToolBar layout on retina displays.

QStyleOptionToolButton::iconSize will be 2x on retina
displays. The layout size should not be 2x however,
that causes excessive spacing in the toolbar.

Task-number: QTBUG-34484
Change-Id: I48cf47044af5b76f39e08c1d580034b84ef2755d
Reviewed-by: Gabriel de Dietrich <gabriel.dedietrich@digia.com>
BlackBerry: Prevent superfluous removal of socket notifiers

File descriptors have always been removed from bps before adding them,
which lead to an annoying warning.
"QEventDispatcherUNIX::registerSocketNotifier()" needs to be called
after "ioEvents()" to prevent this.

Back-port of qtbase/e9c51a1fdc9092e5589fd6f823ad0e704e293c88

Task-number: QTBUG-34536

Change-Id: I767a15cb2883bc820da5c858613ffb26abc002e4
Reviewed-by: Thomas McGuire <thomas.mcguire@kdab.com>
Reviewed-by: Petr Nejedlý <pnejedly@blackberry.com>