add tests for JPEG endpoint
add tests for JPEG endpoint

kod3r/splash,Youwotma/splash,dwdm/splash,kod3r/splash,kmike/splash,pombredanne/splash,pawelmhm/splash,kod3r/splash,dwdm/splash,dwdm/splash,pombredanne/splash,kmike/splash,pawelmhm/splash,Youwotma/splash,pombredanne/splash,Youwotma/splash,kmike/splash,pawelmhm/splash