Merge pull request #821 from junamai2000/develop

Add support for Cache-Control header

Reviewed-by: kuenishi
add cluster-info
add riak-cs-cinfo to package_commands.
Merge pull request #829 from basho/feature/cluster-info

Add cluster-info

Reviewed-by: kuenishi
add riak-cs-debug
Merge pull request #832 from basho/feature/riak-cs-debug

Add riak-cs-debug

Reviewed-by: kuenishi
add a test case for cache-control header