tests, don't write TS_DEVICE to stdout anymore
tests: introduce TS_CMD_UUIDGEN (never use installed one)

Signed-off-by: Ruediger Meier <ruediger.meier@ga-group.nl>
travis-ci: minor cleanup and speedup

Signed-off-by: Ruediger Meier <ruediger.meier@ga-group.nl>
travis-ci: enable root checks

Signed-off-by: Ruediger Meier <ruediger.meier@ga-group.nl>