Support external ExecuteProcess output overrides. (#218)
Support external ExecuteProcess output overrides. (#218)

* Support external ExecuteProcess output overrides.

By means of an $OVERRIDE_LAUNCH_PROCESS_OUTPUT envvar.

Signed-off-by: Michel Hidalgo <2c7f9fd20fbeb41ce8894ec4653d66fa7f3b6e1a@ekumenlabs.com>

* Address peer review comments.

Signed-off-by: Michel Hidalgo <2c7f9fd20fbeb41ce8894ec4653d66fa7f3b6e1a@ekumenlabs.com>

ros2/launch,ros2/launch,ros2/launch