Adding changes to SecondaryIndex.cs base class for Add overrides
Adding changes to SecondaryIndex.cs base class for Add overrides


Former-commit-id: 2e3b220d205f7ac717a69b2cdcc233f07632b738
basho/riak-dotnet-client,rob-somerville/riak-dotnet-client,basho/riak-dotnet-client,rob-somerville/riak-dotnet-client