repoint to riak_api with webmachine with L17 test fix

rebar.config

@@ -38,7 +38,7 @@
         {eunit_formatters, ".*", {git, "git://github.com/seancribbs/eunit_formatters", {tag, "0.1.2"}}},
         {kv_index_tictactree, ".*", {git, "https://github.com/martinsumner/kv_index_tictactree.git", {tag, "0.9.21"}}},
         {riak_core, ".*", {git, "https://github.com/TI-Tokyo/riak_core.git", {tag, "riak_kv-2.9.2+mas-i1801-coverageplan"}}},
-        {riak_api, ".*", {git, "git://github.com/basho/riak_api.git", {tag, "riak_kv-2.9.2"}}},
+        {riak_api, ".*", {git, "https://github.com/TI-Tokyo/riak_api.git", {tag, "riak_kv-2.9.2-graviton2"}}},
         {hyper, ".*", {git, "git://github.com/basho/hyper", {tag, "1.0.1"}}},
         {riakhttpc, ".*", {git, "git://github.com/basho/riak-erlang-http-client", {tag, "riak_kv-2.9.2"}}}
        ]}.