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/transactiontablemodel.h

@@ -14,6 +14,7 @@ class WalletModel;
 class TransactionTableModel : public QAbstractTableModel
 {
     Q_OBJECT
+
 public:
     explicit TransactionTableModel(CWallet* wallet, WalletModel *parent = 0);
     ~TransactionTableModel();
@@ -55,6 +56,7 @@ public:
     QVariant data(const QModelIndex &index, int role) const;
     QVariant headerData(int section, Qt::Orientation orientation, int role) const;
     QModelIndex index(int row, int column, const QModelIndex & parent = QModelIndex()) const;
+
 private:
     CWallet* wallet;
     WalletModel *walletModel;