Move webmachine to riak_api.
Remove mostly-unused riak_core_config.
Copy in mochiglobal as riak_core_mochiglobal.
Move json_pp to riak_kv.
Remove default_bucket_props/0 that is unnecssary with bucket-types.
Merge pull request #381 from basho/refactor/sdc-wm-move

Remove webmachine dependency