What are those new files after Activator 1.3.5 update? <p>Today while starting my Play app with <code>activator run</code> the new Activator version 1.3.5 got installed automatically. My app's running perfectly fine. But now I see a couple of new files in my app's folder and I don't know what they are or how to handle them. Maybe someone can advice me. Google didn't help me much so far. Those files are </p> <ul> <li>.sbtserver</li> <li>.sbtserver.lock</li> <li>play-fork-run.sbt</li> <li>sbt-ui.sbt</li> </ul> <p>Except for the .sbtserver.lock they all look like configuration files. But what are they configuring? And should I put them under version control?</p>