Review and ensure metadata is correctly set and transport

[skyao]

Expected Behavior

metadata should be correctly set and passed to dapr.

Actual Behavior

At first, in state save method, there is no metadata to set.

See file src/main/java/io/dapr/client/domain/State.java

I will submit a PR for this and later check other processes.

RELEASE NOTE: RESOLVED validated handling of metadata and fixed when applicable.

[skyao]

@artursouza Another PR has raised to add metadata parameter in get bulk request which is missing in java sdk.

#401

Please help to review. And now I only updated the grpc api.

For HTTP API, should we also support metadata in get bulk request (and also there is a ongoing PR to add metadata in get/bulk get response)?

[skyao]

@artursouza A new more PR for metadata just raised.

[artursouza]

@skyao Thanks a lot. I will review the PR. Please, keep feature parity for the GRPC and HTTP clients for Dapr.

[artursouza]

I am handling all the remaining metadata logic in the PR above.