adding DISPLAY_ARTICLE_INFO_ON_INDEX option
Merge branch 'article_info_on_homepage' of https://github.com/toumorokoshi/pelican-bootstrap3 into toumorokoshi-article_info_on_homepage

* 'article_info_on_homepage' of https://github.com/toumorokoshi/pelican-bootstrap3:
  adding DISPLAY_ARTICLE_INFO_ON_INDEX option
Clarification of article info on index