dev: Removed the obsolete methods - Create<T>, Freeze<T>.
dev: Removed the obsolete types.

- TestFixtureConfigurationAttribute
- AutoFixtureConfigurationAttribute
dev: Removed the obsolete method 'CreateFixture'.
dev: Renamed NullGuardClauseAssertion to GuardClauseAssertion.
docs: Addressed release notes for v2.
dev: Removed the obsolete property 'ActualMethod'.
dev: Removed the contructor 'TestCase2(MethodInfo, object[])'.
dev: Removed the obsolete property 'TestCommandContext.TestObject'.
dev: Removed the FirstClassTestAttribute class.
dev: Removed ITestCase and TestCase.
dev: Removed the FirstClassCommand class.
dev: Remove TestAttribute.
dev: Removed AutoPropertiesAttribute.
dev: Removed FrozenAttribute.
dev: Removed FrozenAttribute.
dev: Removed ModestAttribute.
dev: Removed NoAutoPropertiesAttribute.
dev: Removed CustomizeAttribute.
dev: Removed TestFixtureConfigurationAttribute.
dev: Removed DefaultFixtureConfigurationAttribute.