Fix Null Reference Exception in PersonState.ReadSpouse

Null Reference Exception no longer thrown when PersonState.GetSpouseRelationships returns null (no spouse).
More readme updates.
Added missing qualifier components.
Ported fact example tests.
Modified qualifier QName resolution.
Converted to use XmlEnum attributes.
Added new example test.
Adding missing fluent methods and constructors.
Ported name example test.
Ported example test.
Ported example test.
Ported last example test.
Added XML docs.
Added XML comments
Added XML docs.
XML documentation updates.
Standardized XML documentation for Clone()
Added standard LoadEntityConditionally() XML documentation.
Added standard LoadEntity() XML documentation.
Added XML documentation.