[DP-6] new proto entries to enable pb API for API entry points coverage

This branch (see PR #105) is
based on
basho/riak_pb/feature/zl/add-pb-req-resp-for-active-annoated-preflist.

There is a matching commit in basho/riak_kv in a newly created branch
feature/az/api-entrypoints-coverage.

src/riak_kv.proto

@@ -272,3 +272,19 @@ message RpbCounterGetReq {
 message RpbCounterGetResp {
     optional sint64 value = 1;
 }
+
+// ring API entry points coverage request
+message RpbApiEntryPointsReq {
+    required bytes bucket = 1;
+    required bytes key = 2;
+    enum RpbApiProto {
+        PB = 0;
+        HTTP = 1;
+    }
+    optional RpbApiProto proto = 3 [default = PB];
+}
+// ring API entry points coverage response
+message RpbApiEntryPointsResp {
+    required bytes host = 1;
+    required int32 port = 2;
+}

src/riak_pb_messages.csv

@@ -50,6 +50,8 @@
 81,DtFetchResp,riak_dt
 82,DtUpdateReq,riak_dt
 83,DtUpdateResp,riak_dt
+90,RpbGetApiEpReq,riak_kv
+91,RpbGetApiEpResp,riak_kv
 253,RpbAuthReq,riak
 254,RpbAuthResp,riak
 255,RpbStartTls,riak