Refactor the client (again) to better support auth

* Allows consumers to provide their own transports for common cases.
* Supports KUBE_API_VERSION on test cases for controlling which
  api version they test against
* Provides a common flag registration method for CLIs that need
  to connect to an API server (to avoid duplicating flags)
* Ensures errors are properly returned by the server
* Add a Context field to client.Config
Minor point about assigned reviews
Merge pull request #1526 from thockin/docs

Minor point about assigned reviews
Merge pull request #1500 from smarterclayton/refactor_client_again

Refactor the client (again) to better support auth
A Dockerfile that builds an image for sending Docker log files
to Eleasticsearch, a config file for fluentd and some helpful
shell scripts.
Moving contrib/fluentd-elasticsearch to contrib/logging/fluentd-elasticsearch
Remove small shell utilities, apply comments in pull request, add README.md
A Dockerfile that builds an image for sending Docker log files
to Eleasticsearch, a config file for fluentd and some helpful
shell scripts.
Moving contrib/fluentd-elasticsearch to contrib/logging/fluentd-elasticsearch
Remove small shell utilities, apply comments in pull request, add README.md
Revert "A Dockerfile that builds an image for sending Docker log files"

This reverts commit d20725749ae03fa6491493a4f8bca7f89efe0e5b.

Conflicts:
	contrib/logging/fluentd-elasticsearch/Dockerfile
	contrib/logging/fluentd-elasticsearch/td-agent.conf
Merge branch 'master' of github.com:satnam6502/kubernetes