v6.1.0beta-20230831

6.1.0beta

• Unify status headers for backend errors. All backends now generate the
  following headers on error:
  • X-RESTfm-Backend: {backend}
  • X-RESTfm-Backend-Status: ...
  • X-RESTfm-Backend-Reason: ...
• The new headers replace per-backend naming of headers which looked like:
  • X-RESTfm-{backend}-Status: ...
  • X-RESTfm-{backend}-Reason: ...
• Add "enableLegacyStatusHeaders" configuration option (see RESTfm.ini) to
  assist client software not yet aware of the new backend status headers.