### Summary
After the addition of the tap APIServer, all the logic related to tap in the public API no longer needs to be there. The servers and clients that are created but not used, as well as all the old testing infrastrucure related to tap can be removed.
This deprecates TapByResource and therefore required an update to the protobuf files with `bin/protoc-go.sh`. While the change to deprecate this method was extremely small, a lot of protobuf fils were updated in the process. These changes to the code and protobuf files should probably remain coupled since `TapByResource` is officially deprecated in the public API, but a majority of the additions/deletions are related to those files.
This draft passes `go test` as well as a local run of the integration tests.
Signed-off-by: Kevin Leimkuhler <kleimkuhler@icloud.com>
This PR begins to migrate Conduit to Linkerd2:
* The proxy has been completely removed from this repo, and is now located at
github.com/linkerd/linkerd2-proxy.
* A `Dockerfile-proxy` has been added to fetch the most-recently published proxy
binary from build.l5d.io.
* Proxy-specific protobuf bindings have been moved to
github.com/linkerd/linkerd2-proxy-api.
* All docker images now use the gcr.io/linkerd-io registry.
* `inject` now uses `LINKERD2_PROXY_` environment variables
* Go paths have been updated to reflect the new (future) repo location.
protobuf has a `go_package` option that can be used to explicitly name
Go packages such that they can be imported without additional rewrites.
This allows us to store proto files without additional, redundant
directories (which were used for packaging hints, previously).
This change adds an explicit `go_package` to all .proto files and
updates `bin/protoc-go.sh` to ensure these packages are output into
$GOPATH (so that the go_package can be absolute). This removes the need
to manually rewrite imports in bin/protoc-go.sh.