Print build id when triggering the systemtests

[fsimonis]

When an adapter triggers a systemtest, there is no explicit reference to the resulting build id.
The trigger script should print it here:

systemtests/trigger_systemtests.py

Lines 217 to 219 in 546279f

	job_id = request_info['builds'][0]['id']
	job_status = ''

Related to #104