Simplify SequenceOf.any implementation
Rename Sequence.swift to SequenceOf.swift

Also rename 2 test files to match other tests.
Add Array.lazy

It’s especially useful when used with SequenceOf lazy methods, like:
array.lazy.filter { … }
Property is used, because there is no conversion or movement of
elements, and for nicer method chaining.
Added SequenceOf.toArray

It’s especially useful with method chaining. Forms a nice pair with
Array.lazy. One can do: array.lazy.someLazyOperations().toArray().
Quick fix