Makes all methods of the IEnumerableFluentAssertion interface returning IChainableFluentAssertion<IEnumerableFluentAssertion> instances.
Fixes the missing documentation tags within the IEnumerableFluentAssertion & EnumerableFluentAssertion types.
Fixes the DevDoD.md file indicating that every assertion method should return a chainable assertion.
Removes an obsolete TODO.
Updates the backlog.