- Fixes#901.
## Type of Change
- [x] Bug fix
- [x] New feature
- [ ] Breaking change
- [ ] Documentation update
## Motivation and Context
Previously `container image prune` called `ImageStore.prune()` (renamed
to `cleanupOrphanedBlobs()` in cz 0.15.0) which only removed orphaned
content blobs and never actually removed images.
This PR fixes that behavior so `container image prune` removes dangling
images by default, and with `-a` removes all unused images, not just
dangling ones.
## Testing
- [x] Tested locally
- [ ] Added/updated tests
- [ ] Added/updated docs
- Part of #515.
- Order options alphabetically.
- Use consistent descriptions for platform, os, arch.
- Add os/arch options to push.
- Rename ImageRemove to ImageDelete since delete is the primary command
and rm is the alias.
## Motivation and Context
Clear, consistent presentation of command help.
Raj