WhereParallel added
SelectParallel added
AnyWithParallel
Queryable->Query & ParallelQuery, added .AsParallel(), .AsSequential()
separate plinq and its tests, fix: parallel query methods to return ParallelQuery
optimization: early termination for All
All (parallel)
AsOrdered, AsUnordered (for parallel)
fix: make AsUnordered really unordered
Single (parallel)
CountBy, Count, Any (parallel query)