CodePaster: Do better checking on hosts.

Do an initial connection check on the host
(once per host). Add utility function to
NetworkProtocol, displaying connection check
message box.
Move the 'Paste' handling into the PasteView
dialog, such that the checking happens there
and the dialog stays open if something fails.

Task-number: QTCREATORBUG-2117

src/plugins/cpaster/pasteview.h

@@ -42,6 +42,7 @@ class PasteView : public QDialog
     Q_OBJECT
 public:
     explicit PasteView(const QList<Protocol *> protocols,
+                       const QString &mimeType,
                        QWidget *parent);
     ~PasteView();
 
@@ -56,6 +57,8 @@ public:
     QByteArray content() const;
     QString protocol() const;
 
+    virtual void accept();
+
 private slots:
     void contentChanged();
     void protocolChanged(int);
@@ -63,6 +66,7 @@ private slots:
 private:
     const QList<Protocol *> m_protocols;
     const QString m_commentPlaceHolder;
+    const QString m_mimeType;
 
     Ui::ViewDialog m_ui;
     FileDataList m_parts;