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/addresstablemodel.h

@@ -14,6 +14,7 @@ class WalletModel;
 class AddressTableModel : public QAbstractTableModel
 {
     Q_OBJECT
+
 public:
     explicit AddressTableModel(CWallet *wallet, WalletModel *parent = 0);
     ~AddressTableModel();