Add examples for Deque and OrderedSet

[timarutun]

Description of Changes: Two code examples have been added to demonstrate the usage of Deque and OrderedSet data structures:

For Deque, an example was created that shows how to add elements from both ends and remove them, demonstrating its functionality.
For OrderedSet, an example was added to show how to work with unique elements while maintaining insertion order, including operations for adding and removing elements.
Rationale for Changes: The addition of examples helps users quickly understand how to use these data structures and improves the project's documentation. These changes can be particularly helpful for beginners and developers looking for code examples

Checklist

• I've read the Contribution Guidelines
• My contributions are licensed under the Swift license.
• I've followed the coding style of the rest of the project.
• I've added tests covering all new code paths my change adds to the project (if appropriate).
• I've added benchmarks covering new functionality (if appropriate).
• I've verified that my change does not break any existing tests or introduce unexplained benchmark regressions.
• I've updated the documentation if necessary.

[lorentey]

These look good to me, thanks!

I wonder if Documentation/ is the best place for these -- with the advent of DocC, I think we would prefer to collect such things in the package's docset, rather than in standalone files.