Added some helper extension methods for Projecting and Grouping when wanting to use a BsonDocument, likely the most common need.
internalize the conversion of an Expression<Func<T, bool>> into a predicate so as to be allow composition of expression trees and not have the compiler choose the wrong overload.
fixed Out method in Aggregate api that didn't behave as it should.
added more missing ConfigureAwaits.
making some api fixes and additions.
IFindFluent extension methods were extending the concrete type.
CSHARP-1108: changed storage options to storage engine.
chagned Test target in build script to show the test labels.
ignoring MapReduceOutputToCollection test on sharded servers.