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/sendcoinsdialog.cpp

@@ -1,5 +1,6 @@
 #include "sendcoinsdialog.h"
 #include "ui_sendcoinsdialog.h"
+
 #include "walletmodel.h"
 #include "bitcoinunits.h"
 #include "addressbookpage.h"
@@ -10,7 +11,6 @@
 #include "base58.h"
 
 #include <QMessageBox>
-#include <QLocale>
 #include <QTextDocument>
 #include <QScrollBar>