grim/convey

Merged in efritz/convey/env-loop-nice-try (pull request #33)

Fix infinite expanion with self-reference (not mutual reference).

Approved-by: Gary Kramlich
options:
ssh-identities:
- '*'
tasks:
dump-env:
image: convey/env
plans:
default:
stages:
- name: dump-env
tasks:
- dump-env