Log Message:
pkgtools/url2pkg: update to 19.3.0

Changes since 2.37:

* Test dependencies in Perl MakeMaker modules are copied to the
  package Makefile.

* Unknown dependencies in Perl MakeMaker modules no longer abort url2pkg
  but instead are added as "# TODO" dependencies to the package Makefile.

* The license from Perl MakeMaker and Python modules is copied to the
  package Makefile.

* The build dependencies, COMMENT and HOMEPAGE from Python setuptools
  modules are copied to the package Makefile.

* No more "undefined $url" when running url2pkg in a directory that
  already has a package Makefile and is extracted.