v0.4.0

Changelog

• dfee97d feat(exec): delete the --create'd branch when the job is cancelled; --timings prints per-phase durations, engine and database
• b1ab176 feat(templates): pgrun template create/list/get/build/delete; branch create/exec --template and --schema-only
• e231425 fix(exec): a command killed by a signal exits 128+signal (143/130), not 255