title: SubSonic connection string for SQLite
body: <p>I'm writing a desktop app which needs a simple persistence layer - I found out about SubSonic and it's capability to work with SQLite. However I need to keep the database file in user's AppData folder and don't know how to put such value into app.config - I don't want to use absolute paths.</p>
  
  <p>Can app.config somehow access enviroment variables or reference application data folder?</p>