<lead>, <developer>, <contributor>, and <helper> -- Developer documentation for a release
Documenting who develops a package
   In package.xml 1.0, a developer was documented using the <maintainer> tag inside of
   a redundant <maintainers> container tag.  This has been simplified in package.xml 2.0
   both to slightly speed parsing and to make validation of the xml simpler.  Now, the contents
   of the <role> tag has been extracted as 4 tags to describe the maintainers of a package.
  
   In addition, a new internal tag <active> has been added, so that you can honor retired
   developers' work without having to remove them altogether from package.xml.
  
   WARNING: tag order is important.  List leads followed by developers followed
   by contributors and finally helpers.