Fix tagged sharding, which was broken in a couple ways: 1. Bad use of $each with $addToSet 2. Using write concern of 'majority' automatically, when shards may not be replica sets.
Fix tagged sharding, which was broken in a couple ways:
1. Bad use of $each with $addToSet
2. Using write concern of 'majority' automatically, when shards may not be replica sets.

llvtt/mongo-orchestration-1,llvtt/mongo-orchestration-1,10gen/mongo-orchestration,10gen/mongo-orchestration