* Load proto_library() rule.

Starting with Bazel 3.0, all Protobuf rules will require explicit load
statements.

Fixes #215.

* More fixes.

* Change versions at random in the hope that one will work.

* Update grpc and load its deps.

* Refer to @rules_proto.

* Update checksum.

This is so that Envoy can consume opencensus-proto without adding
a dependency on grpc_java.

This was added in #176 then reverted in #207.

* Add grpc-gateway for metrics service.

* Add a missing gateway_out.

* Set up Python packaging for PyPI release.

* Remove namespace packages for */v1.

* Remove redundant dependency.

* Use Python style version and update commands.

* Add PyPI badge to README.

* Add scripts to generate python files from proto.

* Run scripts.

* Added ruby proto file generator and generated proto files

* Added releasing instructions for ruby

This reverts commit 853d694f.

Fixes #180.

Fixes #179.

* Add Resource to Span

* Add missing import

* Update to correct id and increment next id

* PR comments

* Add resource to bazel build dep

* Add another dependency

* PR comments

* time is required

* handle case when only end_time was set

This fixes the build (REPOSITORY_NAME error) with bazel 0.21.
(and reverts the workaround from #165)

grpc did the same thing: https://github.com/grpc/grpc/issues/17564

* Minor fixes

* Update trace.proto

* addressed code review feedback