Swagger-UI 3.9.0 Released!

Interface changes: one core plugin API change, no public API changes.

Introduced a breaking function signature change to errActions.newThrownErr action creator (from (err, action) to (err)) and err_new_thrown_err action payload (stopped nesting error content under error key in payload, now the error is the payload).

• Feature: added error catcher for statePlugin interfaces; prevents errors in plugin code from crashing entire application instance (via #4067)
  • The only downside to this is that some errors are now a bit harder to trace! Set a breakpoint at console.error and walk down the stack to see what's going wrong.
• Feature: display error content when definition/config load fails (via #4069)
• Feature: display parameter enums, defaults, and examples when not in Try-It-Out mode (via #3977)
• Improvement: added hasOwnProperty checks to a handful of for...in loops (via #4043)
• Improvement: now using nginx location to set Docker base url instead of moving things around the filesystem (via #4073)
• Improvement: brought parameter model property description styling in line with styling for.... everything else (via #4075)
• Bugfix: check for Promise on global/window object, which makes IE11 a very happy browser (via #4077)
• Housekeeping: used zopflipng to compress PNG assets in repo (via #4037)
• Housekeeping: added maintainer documentation for PR merging workflow (via #4076)