Modbus: allows modbus thread stack size customization with MODBUS_STACK_SIZE macro.

For example, add "-DMODBUS_STACK_SIZE=0x2000" to target CFLAGS to limit stack size to 128kB

#!/bin/bash

set -e

CONTAINER=beremiz_sikuli_current

docker stop $CONTAINER
docker start $CONTAINER 
docker exec $CONTAINER bash -c "do_tests $1"
docker stop $CONTAINER