import endpoints not covered in api docs

[jaffee]

We should take a look at the API Reference section of our docs and make sure we cover anything which implemented in the clients. I know some things we don't want to officially expose and support, but /import and import-value are pretty widely used at this point..

[travisturner]

@codysoyland is going to review the import endpoints again to determine if it makes sense to consolidate them into one.

[yuce]

Is this still good to work on ?

[codysoyland]

We've had a little discussion about combining the two import urls into a singular handler and locking down the API. I still feel like that might be the best option, but I haven't looked at it in a while. I would like to make that decision before documenting them.

[travisturner]

We don't have an import-value endpoint anymore, but we have since added import-roaring. I think this issue is still valid and API updates are needed.