doc: Clarify effect of QFont::NoFontMerging
doc: Clarify effect of QFont::NoFontMerging

There have been reports of several people who expect
QFont::NoFontMerging to turn off all automatic resolution of fonts
when displaying text. However, the flag only turns off automatic
font resolution within a script item. Suitable fonts for scripts not
supported by the current font are still picked automatically. We cannot
change the behavior of QFont::NoFontMerging, so the documentation has
been made clearer and task QTBUG-9816 has been created to implement a
new style strategy flag that supports the use case.

Task-number: QTBUG-1732
Reviewed-by: Trond

pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,igor-sfdc/qt-wk,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt,igor-sfdc/qt-wk,igor-sfdc/qt-wk,pruiz/wkhtmltopdf-qt