Change the way the logging is made quiet in server.js

[julienw]

Currently we shut down the logging if we're in the test environment (see

sensorweb-server/src/server.js

Line 32 in 1da3319

if (config.get('env') !== 'test') {

). This is both fragile and not effective -- for example it's still used in circleci.

Instead we should use an env variable to control this. One possibility is to shush it when using the env vairable QUIET.