fix column number displayed for an empty buffer

src/gui/BufferPane.cc

@@ -7,6 +7,7 @@ BufferPane::BufferPane(Window * window, std::shared_ptr<Buffer> buffer)
     m_scroll_offset = 5;
     m_iterator = buffer->add_iterator();
     m_target_column = 0;
+    m_cursor_virtual_column = 0;
 }
 
 void BufferPane::resize(int width, int height)