* fix: Correct flatten function in layers
- Added a test.
- Cache current image, track deletes in `whiteouts` as well as normal adds in `layers`.
- Fix ugly delete behavior of `layerHashCache`.
Delete it when crerating a new snapshot.
- Slight cleanup in `snapshot.go`.
- Format ugly `WalkFS` function.
* fix: Add symbolic link changes to Hasher and CacheHasher
* fix: Better log messages
* fix(ci): Integration tests
* fix(ci): Add `--no-cache` to docker builds
* fix(ci): Pass credentials for error integration test
* np: Missing .gitignore in `hack`
* np: Capitalize every log message
- Correct some linting.
* fix: Key function
- Merge only last layer onto `currentImage`.
* fix: Remove old obsolete `cacheHasher`
* Rework cache key generation a bit.
Cache keys are now based on the previous commands, rather than the previous state
of the filesystem.
* Refactor command interface a bit, only cache the context for commands that use it.
CacheCommand returns true if the command should be cached. Currently,
it's only true for RUN but can be added to ADD/COPY later on (these are
different since the contents of files for ADD/COPY need to be included
in the cache key generation).
I also changed CreatedBy to String so that we can log each command
before cache extraction or regular execution takes place.
* Vendor changes for go-containerregistry switch.
* Manual changes for go-containerregistry switch.
The biggest change is refactoring the tarball unpacking.
* Pull more of container-diff out.
* More vendor removals.
* More unit tests.