Re-insert the previously deleted line.

def reverseCommit(self):
        """
        Re-insert the previously deleted line.
        """

        # Get the text cursor for the current document.
        tc = self.qteWidget.textCursor()

        # Re-insert the deleted text at the correct position.
        tc.setPosition(self.cursorPos0)
        tc.insertHtml(self.killedText)

        # Apply the changes.
        self.qteWidget.setTextCursor(tc)