Reverse dependencies for hash-joiner

Latest version of the following gems require hash-joiner

Gem	Version	Date	Downloads
team_api +31.6 Thousand Downloads	`0.0.13` March 15, 2016	March 15, 2016	31.6 Thousand
team_hub +19.5 Thousand Downloads	`0.0.6` March 26, 2015	March 26, 2015	19.5 Thousand
jumbo-jekyll-theme-test +8.56 Thousand Downloads	`1.0.4` August 15, 2018	August 15, 2018	8.56 Thousand
jekyll-pubmed +5.54 Thousand Downloads	`0.1.2` January 27, 2017	January 27, 2017	5.54 Thousand