* Use `quay.io/dghubble/protoc` as the standard codegen
environment across projects. Pin a version (v3.10.1)
* Generated code is now automatically ignored by golint
based on the comment header, which will simplify linting
* Upgrade protobuf from 2bba0603135d to v1.3.2
* Upgrade grpc from v1.2.1 to v1.25.1
* Remove `get-protoc` and `codegen` scripts
* Matchbox has moved to a new home in Poseidon
* Update Makefile so container image name uses
poseidon instead of coreos
* Publish container images to quay.io/poseidon/matchbox
* Render Container Linux Configs referenced in Profiles
as Ignition v2.2.0 documents.
* Recall, configs suffixed with .ign/.ignition will be
served as-is, as raw Ignition. Parse warnings will be
shown
* Serve Ignition configs (ending in .ign/.ignition) with v2.1
or v2.2 formats (previously, configs above v2.1 produced warnings
that the config was too new)
* Use Go 1.11 modules with `GO111MODULE=on`
* Change `make vendor` target to call `go mod vendor`
* Enforce builds and tests use the vendor directory by setting
the `-mod=vendor` flag (notice, travis does not fetch)
* Remove glide requirement and glide files
