Corrects the `ToArray` method in `GenericEnumerableEquivalencyStep`.
Treating the enumerable as its most derived type was unnecessary as the method being invoked only only accepts the `IEnumerable<T>` interfaces.  In some cases, such as assertions on LINQ queries, this unnecessary behavior was fatal.
Renames CollectionEquivalencySpecs to EnumerableEquivalencySpecs.
Done so that it better matches the EquivalencySteps it tests and has less potential to convey that it contains tests for all types of collections.
Does some organization in DictionaryEquivalencySpecs
Moves non-generic dictionary spec and class into proper region, removes unused class.
Moved '(Nested) Dictionaries' region to DictionaryEquivalencySpecs