scripts: Add octopi installation scripts

Add a system startup script so that Klipper can automatically start at
boot time.  Create an installation script that will install the system
dependencies and the startup script.

Signed-off-by: Kevin O'Connor <kevin@koconnor.net>

scripts/klipper-start.sh

@@ -0,0 +1,54 @@
+#!/bin/sh
+# System startup script for Klipper 3d-printer host code
+
+### BEGIN INIT INFO
+# Provides:          klipper
+# Required-Start:    $local_fs
+# Required-Stop:
+# Default-Start:     2 3 4 5
+# Default-Stop:      0 1 6
+# Short-Description: Klipper daemon
+# Description:       Starts the Klipper daemon.
+### END INIT INFO
+
+PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
+DESC="klipper daemon"
+NAME="klipper"
+DEFAULTS_FILE=/etc/default/klipper
+PIDFILE=/var/run/klipper.pid
+
+. /lib/lsb/init-functions
+
+# Read defaults file
+[ -r $DEFAULTS_FILE ] && . $DEFAULTS_FILE
+
+case "$1" in
+start)  log_daemon_msg "Starting klipper" $NAME
+        start-stop-daemon --start --quiet --exec $KLIPPY_EXEC \
+                          --background --pidfile $PIDFILE --make-pidfile \
+                          --chuid $KLIPPY_USER --user $KLIPPY_USER \
+                          -- $KLIPPY_ARGS
+        log_end_msg $?
+        ;;
+stop)   log_daemon_msg "Stopping klipper" $NAME
+        killproc -p $PIDFILE $KLIPPY_EXEC
+        RETVAL=$?
+        [ $RETVAL -eq 0 ] && [ -e "$PIDFILE" ] && rm -f $PIDFILE
+        log_end_msg $RETVAL
+        ;;
+restart) log_daemon_msg "Restarting klipper" $NAME
+        $0 stop
+        $0 start
+        ;;
+reload|force-reload)
+        log_daemon_msg "Reloading configuration not supported" $NAME
+        log_end_msg 1
+        ;;
+status)
+        status_of_proc -p $PIDFILE $KLIPPY_EXEC $NAME && exit 0 || exit $?
+        ;;
+*)      log_action_msg "Usage: /etc/init.d/klipper {start|stop|status|restart|reload|force-reload}"
+        exit 2
+        ;;
+esac
+exit 0