[skip ci] Add bangs to scripts, add update script

scripts-and-tools/build.sh

@@ -1,3 +1,4 @@
+#!/bin/sh
 # Build script for production
 #
 # No arguments

scripts-and-tools/start.sh

@@ -1,3 +1,4 @@
+#!/bin/sh
 # Startup script for production
 #
 # $1: Server to start; case sensitive!!!!!

scripts-and-tools/update.sh

@@ -0,0 +1,12 @@
+#!/bin/sh
+# Update script for production
+#
+# No arguments
+# Called manually
+
+sudo systemctl stop project-lighthouse*
+
+cd /srv/lighthouse || return
+sudo -u lighthouse -i /srv/lighthouse/build.sh
+
+sudo systemctl start project-lighthouse*