Sandesh client SM task needs to be run exclusive to sandesh client

reader and writer tasks. The sandesh client reader task was named
io::ReaderTask which is the same as the collector reader task and
hence in high scale the sandesh client SM task would be in deferq
and not run since a lot of io::ReaderTask would always be running.
This causes collector statistics to not be sent. Fix is to rename
the sandesh client reader task to sandesh::SandeshClientReader.
Partial-Bug: #1469919

Change-Id: I728d7054d3d1d14c3fca3dc6e0d961c3090a616a

library/cpp/sandesh_client.cc

@@ -40,7 +40,7 @@ using boost::system::error_code;
 
 const std::string SandeshClient::kSMTask = "sandesh::SandeshClientSM";
 const std::string SandeshClient::kSessionWriterTask = "sandesh::SandeshClientSession";
-const std::string SandeshClient::kSessionReaderTask = "io::ReaderTask";
+const std::string SandeshClient::kSessionReaderTask = "sandesh::SandeshClientReader";
 bool SandeshClient::task_policy_set_ = false;
 const std::vector<Sandesh::QueueWaterMarkInfo> 
     SandeshClient::kSessionWaterMarkInfo = boost::assign::tuple_list_of