Add protos
protos for MongoCollection
PHP-659: Revise proto language in collection.c
Merge pull request #355
Fixed PHP-759: Write operations apply ReadPreferenceTags when finding primary
Merge pull request #409
Add ReplicaSet tags for sharded environment
Test ReadPreference and ReadPreferenceTags over mongos
Add GLE with tags for RS and shards
Get rid of some code duplication and move the priority of the master

into make-servers rather then hardcoded in myconfig.js
Slight CS fixups after CR