API: most App exceptions now return json error message

app/api/__init__.py

@@ -4,11 +4,13 @@
 from flask import Blueprint
 from flask import request
 from app.scodoc import sco_utils as scu
+from app.scodoc.sco_exceptions import ScoException
 
 api_bp = Blueprint("api", __name__)
 api_web_bp = Blueprint("apiweb", __name__)
 
 
+@api_bp.errorhandler(ScoException)
 @api_bp.errorhandler(404)
 def api_error_handler(e):
     "erreurs API => json"