added core macros plugin with initial article_list macro
added wiki-article-list class to article_list macro template
added wiki-article-sublist class to article_list macro template
added Django 1.5 url syntax to macros plugin; added condition to avoid generating empty lists for each child in article_list macro
fixed article_list macro sublist markup
restructured url resolver in article_list macro
Merge pull request #105 from SacNaturalFoods/master

added core macros plugin with initial article_list macro