New candidate JEP: 505: Structured Concurrency (Fifth Preview)

[Mark Reinhold]

// Resending to loom-dev at openjdk.org, since the address
// in the original announcement was incorrect

https://openjdk.org/jeps/505

  Summary: Simplify concurrent programming by introducing an API for
  structured concurrency.  Structured concurrency treats groups of
  related tasks running in different threads as single units of work,
  thereby streamlining error handling and cancellation, improving
  reliability, and enhancing observability.  This is a preview API.

- Mark