Close main window after opening connection if there is only one connection

[virl]

When user opens added connection via main window (connection selection window) the window must be closed if there is only one connection.

Also see #63.

[jeromelebel]

Why should the main window be closed?

[virl]

Because if there is only one connection and it is opened, there is no longer any use for main window - user cannot open any other connection (because it doesn't exist) - so it must be closed to free desktop/screen space of user.

For example, look at the Pages app or Xcode app. They too showing "New project/document" window at launch, but only if there is no opened document/project.

[jeromelebel]

This is not an helper or a launcher. This is the only way to open a connection.

[virl]

Connection opened. There is no other connections. Why would main window should be displayed on screen?