remove k8s.io/kubernetes dependency

[cgonyeo]

This commit removes k8s.io/kubernetes as a dependency. The one part of
the repo that we were using, k8s.io/kubernetes/pkg/api/resource, has
been copied to schema/types/resource, and very minimally modified to
work in its new location. A README.md has been added to this new
location describing where the files came from.

This was necessary to avoid a cyclic dependency with the kubernetes
repo.

Fixes #683.

[cgonyeo]

One thing about this I was uncertain about was that I left all of the copyright attributions at the top of the copied in files as Copyright 2014 The Kubernetes Authors, should this be changed?

[s-urbaniak]

woah, thanks!

I guess we can cut a bit more, namely the whole protobuf dependency.

Looking at what this type implements now it seems a bit too much:

 struct type Quantity
    implements encoding/json.Marshaler
 pointer type *Quantity
    implements encoding/json.Unmarshaler
    implements fmt.Stringer
    implements github.com/appc/docker2aci/vendor/github.com/gogo/protobuf/proto.Marshaler
    implements github.com/appc/docker2aci/vendor/github.com/gogo/protobuf/proto.Message
    implements github.com/appc/docker2aci/vendor/github.com/gogo/protobuf/proto.Sizer
    implements github.com/appc/docker2aci/vendor/github.com/gogo/protobuf/proto.Unmarshaler
    implements github.com/appc/spec/vendor/github.com/gogo/protobuf/proto.Marshaler
    implements github.com/appc/spec/vendor/github.com/gogo/protobuf/proto.Message
    implements github.com/appc/spec/vendor/github.com/gogo/protobuf/proto.Sizer
    implements github.com/appc/spec/vendor/github.com/gogo/protobuf/proto.Unmarshaler
    implements github.com/golang/protobuf/proto.Marshaler
    implements github.com/golang/protobuf/proto.Message
    implements github.com/golang/protobuf/proto.Unmarshaler
    implements k8s.io/kubernetes/vendor/github.com/gogo/protobuf/proto.Marshaler
    implements k8s.io/kubernetes/vendor/github.com/gogo/protobuf/proto.Message
    implements k8s.io/kubernetes/vendor/github.com/gogo/protobuf/proto.Sizer
    implements k8s.io/kubernetes/vendor/github.com/gogo/protobuf/proto.Unmarshaler
    implements runtime.stringer

Some of the above are redundant, reducing to:

    implements k8s.io/kubernetes/vendor/github.com/gogo/protobuf/proto.Marshaler
    implements k8s.io/kubernetes/vendor/github.com/gogo/protobuf/proto.Message
    implements k8s.io/kubernetes/vendor/github.com/gogo/protobuf/proto.Sizer
    implements k8s.io/kubernetes/vendor/github.com/gogo/protobuf/proto.Unmarshaler

which all reside in quantity_proto.go. I suggest we delete this file, and thus also get rid of the protobuf dependency. Also I suggest we delete the generated protobuf. Summarizing I would also get rid of those files:

• schema/types/resource/generated.pb.go
• schema/types/resource/generated.proto
• schema/types/resource/quantity_proto.go

This Quantity type is quite involved, using fixed point arithmetic, so I would leave all those tests.

[cgonyeo]

Removed the files you requested

[s-urbaniak]

LGTM

[sttts]

Thanks for the fast solution of the issue! 👍

[cgonyeo]

No problem! Now we should just need a new release to use on the k8s side of this. I'll leave that to someone else to take care of...