Localization for Aeon form defaults

[ctgraham]

Is your feature request related to a problem? Please describe.

Pending development on RockefellerArchiveCenter#240, we need a way to target our preferred Aeon form in requests.

Describe the solution you'd like

We've edited the default DocumentType and we've edited the WebRequestForm for reading room requests.

Describe alternatives you've considered

n/a

Additional context

This local is expected to be transient.