Reverse dependencies for datashift

Latest version of the following gems require datashift

Gem	Version	Date	Downloads
datashift_spree +36.8 Thousand Downloads	`0.5.0` January 06, 2013	January 06, 2013	36.8 Thousand
solidus_datashift +4.56 Thousand Downloads	`0.1.0` February 10, 2018	February 10, 2018	4.56 Thousand
excel_import +2.91 Thousand Downloads	`0` October 07, 2019	October 07, 2019	2.91 Thousand