Log Message:
pkgsrc changes:
  - Updating package for module Devel::StackTrace from 1.20 to 1.21
  - Adjusting meta information:
    * license to ${PERL5_LICENSE}
    * module type to Module::Build
    * remove dependency to devel/p5-Test-Simple - desired version is in
      perl core

Upstream changes:
1.21  Jul 1, 2009

- Overloaded objects which didn't provide a stringification method
  cause Devel::StackTrace to die when respect_overload was
  true. Reported by Laurent Dami. RT #39533.

- Added a frame_filter option which allows for fine-grained control
  over what frames are included in a trace. Based on (but expanded)
  from a patch proposed by Florian Ragwitz. RT #47415.