What's new in 1.1.0-beta4
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* EnumerableExtensions.GroupTopoSort methods
* EnumerableExtensions.TopoSort methods reimplemented using GroupTopoSort
* EnumerableExtensions.TopoSort methods refactoring
* Lazy.Create helpers for type inference
* Enumerable.SelectMany overload with Fn<T>.Self as selector
* NullableHelper.GetValueOrDefault method with default value factory
* ToByteSizeString overloads for Int32
* Fix Resharper markup in Code class
* Fixes and code cleanup