JSON-Schema wrong type for evidence:created_at

[Marcos Sanz]

The spec says

created_at: The time the signature was created as ISO 8601:2004 YYYY-MM-DDThh:mm[:ss]TZD format.

however the schema uses a date type instead of a time

              "created_at": {
                "$ref": "#/definitions/date_type"
              }

‌

[Marcos Sanz]

Fixes issue 1189

→ <<cset f60fc444dc20>>

[Torsten Lodderstedt]

Merged in Marcos-Sanz/fixes-isse-1189-1587703436509 (pull request #27)

Fixes issue 1189

Approved-by: Torsten Lodderstedt [e-mail]

→ <<cset 238b6cadd5f1>>