Go version changed to 1.14.4
Golangci-lint changed to 1.26.0
Bazel version changed to 3.0.0
Bazel rules_go version changed to 0.23.3
Bazel gazelle version changed to v0.21.0
Bazel build tools version changed to 0.25.1
Bazel skylib version changed to 1.0.2
As the number of repos and layers increases, the greater the probability
that layers are duplicated. We dedupe using hard links when content is
the same. This is intended to be purely a storage layer optimization.
Access control when available is orthogonal this optimization.
Add a durable cache to help speed up layer lookups.
Update README.
Add more unit tests.