Add multiplayer test script

util/test_multiplayer.sh

+#!/bin/bash
+dir="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"
+gameid=minimal
+minetest=$dir/../bin/minetest
+testspath=$dir/../tests
+worldpath=$testspath/testworld_$gameid
+configpath=$testspath/configs
+logpath=$testspath/log
+conf_server=$configpath/minetest.conf.multi.server
+conf_client1=$configpath/minetest.conf.multi.client1
+conf_client2=$configpath/minetest.conf.multi.client2
+log_server=$logpath/server.log
+log_client1=$logpath/client1.log
+log_client2=$logpath/client2.log
+
+mkdir -p $worldpath
+mkdir -p $configpath
+mkdir -p $logpath
+
+echo -ne 'client1::shout,interact,settime,teleport,give
+client2::shout,interact,settime,teleport,give
+' > $worldpath/auth.txt
+
+echo -ne '' > $conf_server
+
+echo -ne '# client 1 config
+screenW=500
+screenH=380
+name=client1
+viewing_range_nodes_min=10
+' > $conf_client1
+
+echo -ne '# client 2 config
+screenW=500
+screenH=380
+name=client2
+viewing_range_nodes_min=10
+' > $conf_client2
+
+echo $(sleep 1; $minetest --disable-unittests --logfile $log_client1 --config $conf_client1 --go --address localhost) &
+echo $(sleep 2; $minetest --disable-unittests --logfile $log_client2 --config $conf_client2 --go --address localhost) &
+$minetest --disable-unittests --server --logfile $log_server --config $conf_server --world $worldpath --gameid $gameid
+