Reverse dependencies for ssd

Latest version of the following gems require ssd

Gem	Version	Date	Downloads
mushin +340 Thousand Downloads	`0.62.0` March 30, 2017	March 30, 2017	340 Thousand
utter +67.6 Thousand Downloads	`1.9.0` March 30, 2017	March 30, 2017	67.6 Thousand
mushin_ext_ssd +6.98 Thousand Downloads	`0.3.0` December 18, 2016	December 18, 2016	6.98 Thousand
knuth +3.11 Thousand Downloads	`0.1.0` December 30, 2016	December 30, 2016	3.11 Thousand