Add Searchkick.enable_callbacks instructions on README [ci skip]
Add Searchkick.enable_callbacks instructions on README [ci skip]

karthik-mallavarapu/searchkick,savayg/searchkick,mikelkew/searchkick,incorvia/searchkick,richardking/searchkick,yakovenkodenis/searchkick,yakovenkodenis/searchkick,kevin-klein/searchkick,Ribeiro/searchkick,jprosevear/searchkick,richardking/searchkick,Fablic/searchkick,yardclub/searchkick,yardclub/searchkick,incorvia/searchkick,Xtinct/searchkick,nviennot/searchkick,DmitryKK/searchkick,meetrajesh/searchkick,klebervirgilio/searchkick,jprosevear/searchkick,ankane/searchkick,edatrix/searchkick,Fablic/searchkick,johan--/searchkick,elguapo1611/searchkick,bodiam/searchkick,nviennot/searchkick,pluton-house/searchkick,Pathgather/searchkick,savayg/searchkick,joe1chen/searchkick,bodiam/searchkick,spanner/searchkick,jaredcwhite/searchkick,edatrix/searchkick,bukalapak/searchkick,seuros/searchkick,karthik-mallavarapu/searchkick,st0012/searchkick,seuros/searchkick,mehulkar/searchkick,klebervirgilio/searchkick,mikelkew/searchkick,moneyadviceservice/searchkick,instacart/searchkick,st0012/searchkick,jaredcwhite/searchkick,moneyadviceservice/searchkick,spanner/searchkick,pluton-house/searchkick,kevin-klein/searchkick,giangnguyennet/searchkick,instacart/searchkick,Xtinct/searchkick,Altareq/searchkick,Ribeiro/searchkick,bukalapak/searchkick,mehulkar/searchkick,meetrajesh/searchkick,Altareq/searchkick,joe1chen/searchkick,johan--/searchkick,giangnguyennet/searchkick,DmitryKK/searchkick,elguapo1611/searchkick