Testing FindAndCopyVersioningChild
 - added fixture
 - single test
 - reworked IsSingle()
 - modified cloneable flow, removed a class
 - moved around null objects
 - removed New, pushed it into the proxy factory
Merge branch 'master' into laptop_work

Conflicts:
	VersionCommander.sln.DotSettings
	VersionCommanderTests/DeltaApplicationVisitorFixture.cs
	VersionCommanderTests/PropertyVersionControllerFixture.cs
	VersionCommanderTests/TestingAssists/TestHelper.cs
	VersionCommanderTests/TestingBasicC#Knowhow.cs
	VersioningPropertyBag/Extensions/MsCorLibExtensions.cs
	VersioningPropertyBag/Extensions/TypeExtensions.cs
	VersioningPropertyBag/IVersionControlNode.cs
	VersioningPropertyBag/NullObjects/NullVersionControlNode.cs
	VersioningPropertyBag/PropertyBagVersionController.cs
	VersioningPropertyBag/PropertyVersionDelta.cs
	VersioningPropertyBag/VersionControlNodeBase.cs
	VersioningPropertyBag/VisitorFactory.cs
	VersioningPropertyBag/Visitors/DeltaApplicationVisitor.cs
	VersioningPropertyBag/Visitors/DescendentAggregatorVisitor.cs