Add disclaimer field to obs/forecasts/reports

[wholmgren]

I wonder if some organizations would be more likely to adopt the arbiter (or use it more extensively) if it could automatically print company-specific data confidentially requirements. I'd start with something simple like "this {thing} contains proprietary data from {','.join(organizations)}. As described in the Data Use Agreement this data may not be disclosed without consent." It wouldn't be too hard technically to support an organization-supplied text, but might open a can of worms.

Some organizations might also be interested in a data quality disclaimer (this came up in a trial).