Adjust fold-objects timeout

[reiddraper]

• Revert part of 6e7027e. It is
  preferrable to use the request timeout over gen_server:call timoeuts.
  Further, these timeouts have been removed in the client in the master
  branch.
• Make the fold objects request timeout configurable, using
  fold_objects_timeout.
• Update riakc dependency to get features added in
• Never use infinity request timeouts riak-erlang-client#160
• Update riak_repl_pb_api (to get a consistent dependency on riak_pb)

[shino]

• make test and make pulse pass
• Dialyzer output clean (No new warnings)
• xref
• riak_test tests pass

[shino]

manual test

AFTER

application:set_env(riak_cs, fold_objects_timeout, 100). and s3cmd ls.
Then FIN+ACK came from riak_cs after ~ 100 msec since GET request. Nice!

BEFORE

Setting timeout to 100 at current release/1.4 has NO effect (diff below),
s3cmd ls does recieve successful response.

diff --git a/src/riak_cs_list_objects_fsm_v2.erl b/src/riak_cs_list_objects_fsm_v2.erl
index 32e87a3..5f0ef06 100644
--- a/src/riak_cs_list_objects_fsm_v2.erl
+++ b/src/riak_cs_list_objects_fsm_v2.erl
@@ -358,7 +358,7 @@ make_2i_request(RiakcPid, State=#state{req=?LOREQ{name=BucketName},
             {end_key, EndKey},
-            {timeout, timer:minutes(1)},
+            {timeout, 100},
             {call_timeout, timer:minutes(1) + timer:seconds(10)}],

[shino]

Code looks good.
👍 to merge! Nice work!!