Default implementation of column.IterableOrderedMap

[earwin]

Summary

As discussed in #1402: most of column.IterableOrderedMap use cases can be covered by a simple default implementation.
This pull request aims to provide the implementation.

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[jkaflik]

Thanks @earwin ! Could you provide a minimal unit test for your implementation?

[earwin]

@jkaflik
I had examples modified so they use my impl instead of locally defined, so we already had an e2e test in place.
And there's very little actual code being added.
But if it helps, by all means, there you are : )