mechanism to use real UUIDs in the Test2 suite

 Test2::Plugin::UUID is a module that allows the usage of real UUIDs in the
 Test2 suite.
 .
 Test2 normally uses unique IDs generated by appending pid, thread-id, and an
 incrementing integer. These work fine most of the time, but are not
 sufficient if you want to keep a database of events. in that case a real UUID
 is much more useful.
 .
 Test2::Plugin::UUID can use different backends, listed in order of
 preference:
 .
  * UUID >= 0.35
  * Data::UUID::MT
  * UUID::Tiny
  * Data::UUID
 .
 Cf. Test2::Util::UUID(3pm) for a description of their use cases, and
 instructions for selecting a backend and handling warnings.