Daemon 1.9.6 released

• Bugfix: Correctly handle removed tracepoints when retrieving an updated daemon configuration from the Tideways API. Previously removed tracepoints were stuck in the daemon and incorrectly triggered callgraphs within the extension until the daemon is either restarted or the tracepoint overwritten with a new tracepoint.
• Change: Remove support for PID file handling. This has no practical effect on the use with service managers such as systemd, runit or Docker, which reliably track their child processes.
• Change: Remove support for Tideways 4.