Reverse dependencies for rpeg-markdown

Latest version of the following gems require rpeg-markdown

Gem	Version	Date	Downloads
acts_as_markup +215 Thousand Downloads	`2.0.2` July 21, 2015	July 21, 2015	215 Thousand
easy-doc +5.89 Thousand Downloads	`1.0.0` March 17, 2010	March 17, 2010	5.89 Thousand
acts_as_markup_on +5.57 Thousand Downloads	`1.0.0` October 17, 2013	October 17, 2013	5.57 Thousand
jgm-ecstatic +3.83 Thousand Downloads	`0.0.0` August 11, 2014	August 11, 2014	3.83 Thousand