Bitcoin-Qt: massive header and cpp cleanup

- try to enforce the same style to all Qt related files
- remove unneeded includes from the files
- add missing Q_OBJECT, QT_BEGIN_NAMESPACE / QT_END_NAMESPACE
- prepares for a pull-req to include Qt5 compatibility

src/qt/monitoreddatamapper.cpp

@@ -9,7 +9,6 @@ MonitoredDataMapper::MonitoredDataMapper(QObject *parent) :
 {
 }
 
-
 void MonitoredDataMapper::addMapping(QWidget *widget, int section)
 {
     QDataWidgetMapper::addMapping(widget, section);