Add App::Assixt to tools for module distribution

doc/Language/modules-extra.pod6

@@ -14,6 +14,7 @@ more fun.
 Some modules and tools to help you with generating files that are part
 of a module distribution.
 
+=item L<App::Assixt|http://modules.perl6.org/dist/App::Assixt> The module developer's assistant
 =item L<App::Mi6|https://modules.perl6.org/dist/App::Mi6>     Minimal authoring tool for Perl 6
 =item L<META6|https://modules.perl6.org/dist/META6>        Do things with Perl 6 META files
 =item L<Module::Skeleton|https://bitbucket.org/rightfold/module-skeleton>        Generate a skeleton module