Added publiccode.yml metadata file

Author: costas80

publiccode.yml

@@ -50,9 +50,9 @@ description:
       - Quality control
       - Quality assurance
     screenshots:
-      - https://www.itb.ec.europa.eu/files/screenshots/validator_01_form.png
-      - https://www.itb.ec.europa.eu/files/screenshots/validator_02_report.png
-      - https://www.itb.ec.europa.eu/files/screenshots/validator_03_report_details.png
+      - https://www.itb.ec.europa.eu/files/screenshots/validator_json_01_form.png
+      - https://www.itb.ec.europa.eu/files/screenshots/validator_json_02_report.png
+      - https://www.itb.ec.europa.eu/files/screenshots/validator_json_03_report_detail.png
     videos:
       - https://youtu.be/_e-XFqYZBR0
 legal: