Note: the screenshot can only be taken on the primary display now
(rather than on the display in which the mouse is, as was the case
before).

Due to QWidget::showFullScreen having side-effects on OSX (setting the
dock and menubar to autohide, making it impossible to then set them as
hidden), the calls to that method were replaced with
UBPlatformUtils::showFullScreen(QWidget *). This function then calls
QWidget::showMaximized() on OSX, or QWidget::showFullScreen() on Linux
and Windows.

It is currently still impossible to switch smoothly between showing or
hiding the dock on OSX; current behaviour is to hide it all the time,
even in desktop mode.

Q_WS_MACX -> Q_OS_OSX
Q_WS_MAC -> Q_OS_OSX
Q_WS_WIN -> Q_OS_WIN
Q_WS_X11 -> Q_OS_LINUX

Transparent drawing view is separated as DesktopView and doesn't manages strokes selections and movements.

Show Desktop: "Erase all" button isn't work

Desktop mode is broken
SANKORE-633
Positioning of floating palettes inside layers .

Fixed creation of transparent drawing view.

Improve the rendering of the magnifier

fixed issue SANKORE-574 and font manager is now translated depending on the system lanaguage (linux only but other will be fixed soon too) and some script build issues fixed on linux