Refactored NamespaceFixtures.
Updated version to v4.0.0-beta-build11.
Removed the thread static attribute.
Updated version to v4.0.0-beta-build12.
Refactored some classes.
Refactored SpecimenEngine using thread static.
Refactored SpecimenEngine and NamespaceFixtureTransformer using thread static.
Updated version to v4.0.0-beta-build13.
Improved the UniqueRandomIdGenerator class.
Deleted the ThreadStaticHelper class.
Updated version to v4.0.0-beta-build14.
Deleted the constant 'TEST'.
Refactored some classes.