Cleanup of module structure

* Rename defined type **sunappserver::config::service** to **sunappserver::config::domain**
* Removal of the **imq_home** parameter, as it is always depending on the
  **appserv_installroot** parameter.
* Move the configuration of the domain.xml (for IMQ type) to the
  **sunappserver::config::domain** defined type, as it is a per-domain
  setting.
* Various cleanups and fixes.