Restore Signbank Wiki API Examples page

[susanodd]

Since we're apparently non-specific to Swagger, the deleted (non-Swagger) Signbank Wiki API Examples page must be restored.

The multilingual aspect of the original Wiki has been split into a separate issue to reduce work into smaller chunks for easier review. See #1497

Original issue description follows:

BRING BACK THE EXAMPLES from the lost Wiki API examples page

This is what the examples showed as the right-hand-side of the json data for Senses. This only shows up now if you get an error message.

{"en":[["sense 1 keyword1", "sense 1 keyword2"],["sense 2 keyword1"]], "nl":[["sense 1 keyword1"],["sense 2 keyword1", "sense 2 keyword2"]]}