tests: ts_scsi_debug_init must not run in a subshell

ts_skip and ts_die won't work from subshell. Now we simply use
DEVICE which is still globally set in that function.

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

Sort out global and local vars. We still keep DEVICE global,
see followups.
Skip quiet.

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