Don't connect to the MainWindow

We really shouldn't need to connect to the MainWindow in order to get the
right scale for the fonts when printing. While printing likely will remain
a desktop only function, this is just bad design. And making calls like
this from the paint() function is a bad plan, anyway.

So instead we make sure that every DiveTextItem knows what the printScale
was when it was created (or actually, when the text was first set as they
frequently get created before we have a scene which we use to get to the
profile), and gets updated whenever that scale changes.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

qt-ui/profile/profilewidget2.cpp

@@ -1465,6 +1465,7 @@ void ProfileWidget2::setPrintMode(bool mode, bool grayscale)
 void ProfileWidget2::setFontPrintScale(double scale)
 {
 	fontPrintScale = scale;
+	emit fontPrintScaleChanged(scale);
 }
 
 double ProfileWidget2::getFontPrintScale()