* Refactored server-launching code. pqServerStartup is replaced by
  pqServerConfiguration that better encapsulates a server configuration XML.
* pqServerStartups is replaced by pqServerConfigurationCollection.
* pqServerResources is replaced by pqRecentlyUsedResourcesList which better
  describes the role of this class.
* pqServerConnectDialog is the single dialog that manages all components of
  connecting to a server. All different pages are shown in the same dialog in a
  Wizard-style. Added support to fetch server configurations and edit server
  configuration sources to this dialog.
* pqServerLauncher encapsulates all the logic to launch a server process. It
  also has code to popup a dialog to obtain option values from the user.
* pqServerConfigurationImporter is a new class that encapsulates the logic to
  import server configurations from remote URLs. This is used by
  pqServerConnectDialog to fetch remote configurations available.