extract searcher_class instantiation into module
extract searcher_class instantiation into module

searcher_class was being instantiated in the same way in home_controller
products_controller, and taxons_controller. This moves that code into a
new Spree::Core::ControllerHelpers::Search module.

Fixes #3420

omarsar/spree,groundctrl/spree,miyazawatomoka/spree,jasonfb/spree,sfcgeorge/spree,pulkit21/spree,berkes/spree,Hates/spree,dafontaine/spree,project-eutopia/spree,Hates/spree,mleglise/spree,azclick/spree,Engeltj/spree,jsurdilla/solidus,moneyspyder/spree,Kagetsuki/spree,archSeer/spree,Mayvenn/spree,jaspreet21anand/spree,mleglise/spree,hoanghiep90/spree,caiqinghua/spree,Lostmyname/spree,Engeltj/spree,ckk-scratch/solidus,ahmetabdi/spree,Engeltj/spree,useiichi/spree,kitwalker12/spree,lsirivong/solidus,builtbybuffalo/spree,reidblomquist/spree,camelmasa/spree,Senjai/spree,maybii/spree,siddharth28/spree,mindvolt/spree,maybii/spree,vinayvinsol/spree,ayb/spree,alvinjean/spree,sideci-sample/sideci-sample-spree,surfdome/spree,omarsar/spree,Senjai/solidus,Machpowersystems/spree_mach,APohio/spree,pervino/solidus,Nevensoft/spree,mindvolt/spree,moneyspyder/spree,watg/spree,jimblesm/spree,nooysters/spree,joanblake/spree,maybii/spree,tesserakt/clean_spree,odk211/spree,pervino/spree,jsurdilla/solidus,dafontaine/spree,Nevensoft/spree,sideci-sample/sideci-sample-spree,lyzxsc/spree,assembledbrands/spree,RatioClothing/spree,grzlus/spree,odk211/spree,progsri/spree,softr8/spree,yushine/spree,vmatekole/spree,surfdome/spree,rajeevriitm/spree,FadliKun/spree,rajeevriitm/spree,sunny2601/spree,grzlus/spree,vinsol/spree,priyank-gupta/spree,JuandGirald/spree,Boomkat/spree,alepore/spree,devilcoders/solidus,moneyspyder/spree,bonobos/solidus,jimblesm/spree,cutefrank/spree,volpejoaquin/spree,orenf/spree,net2b/spree,vinayvinsol/spree,LBRapid/spree,camelmasa/spree,Arpsara/solidus,AgilTec/spree,TrialGuides/spree,assembledbrands/spree,reinaris/spree,yushine/spree,fahidnasir/spree,vinsol/spree,KMikhaylovCTG/spree,tancnle/spree,APohio/spree,gregoryrikson/spree-sample,raow/spree,Hawaiideveloper/shoppingcart,pjmj777/spree,dandanwei/spree,ramkumar-kr/spree,APohio/spree,dotandbo/spree,shekibobo/spree,reinaris/spree,JDutil/spree,archSeer/spree,scottcrawford03/solidus,degica/spree,dandanwei/spree,scottcrawford03/solidus,alvinjean/spree,rakibulislam/spree,zaeznet/spree,locomotivapro/spree,progsri/spree,mleglise/spree,devilcoders/solidus,nooysters/spree,Machpowersystems/spree_mach,carlesjove/spree,jsurdilla/solidus,piousbox/spree,useiichi/spree,alepore/spree,quentinuys/spree,shioyama/spree,vulk/spree,archSeer/spree,imella/spree,raow/spree,richardnuno/solidus,siddharth28/spree,grzlus/spree,degica/spree,zamiang/spree,project-eutopia/spree,DynamoMTL/spree,madetech/spree,sunny2601/spree,mindvolt/spree,ckk-scratch/solidus,ayb/spree,FadliKun/spree,lsirivong/spree,azranel/spree,Migweld/spree,jsurdilla/solidus,sfcgeorge/spree,DynamoMTL/spree,pervino/solidus,TrialGuides/spree,bonobos/solidus,thogg4/spree,TrialGuides/spree,cutefrank/spree,hifly/spree,pjmj777/spree,moneyspyder/spree,reidblomquist/spree,rajeevriitm/spree,Arpsara/solidus,dandanwei/spree,welitonfreitas/spree,reinaris/spree,beni55/spree,vcavallo/spree,project-eutopia/spree,wolfieorama/spree,brchristian/spree,biagidp/spree,jspizziri/spree,sliaquat/spree,Lostmyname/spree,njerrywerry/spree,jeffboulet/spree,azclick/spree,forkata/solidus,ujai/spree,raow/spree,cutefrank/spree,wolfieorama/spree,jasonfb/spree,shaywood2/spree,DarkoP/spree,grzlus/solidus,gautamsawhney/spree,surfdome/spree,jaspreet21anand/spree,jeffboulet/spree,alejandromangione/spree,thogg4/spree,karlitxo/spree,ckk-scratch/solidus,PhoenixTeam/spree_phoenix,ayb/spree,delphsoft/spree-store-ballchair,scottcrawford03/solidus,agient/agientstorefront,shioyama/spree,hoanghiep90/spree,trigrass2/spree,softr8/spree,shekibobo/spree,karlitxo/spree,alvinjean/spree,kewaunited/spree,richardnuno/solidus,CJMrozek/spree,caiqinghua/spree,zaeznet/spree,firman/spree,JuandGirald/spree,agient/agientstorefront,JuandGirald/spree,nooysters/spree,vulk/spree,ahmetabdi/spree,rajeevriitm/spree,carlesjove/spree,sunny2601/spree,RatioClothing/spree,Arpsara/solidus,tesserakt/clean_spree,abhishekjain16/spree,madetech/spree,woboinc/spree,trigrass2/spree,lsirivong/spree,delphsoft/spree-store-ballchair,net2b/spree,Hawaiideveloper/shoppingcart,bjornlinder/Spree,joanblake/spree,welitonfreitas/spree,gregoryrikson/spree-sample,dotandbo/spree,locomotivapro/spree,pjmj777/spree,richardnuno/solidus,TimurTarasenko/spree,rakibulislam/spree,zamiang/spree,xuewenfei/solidus,SadTreeFriends/spree,AgilTec/spree,robodisco/spree,tesserakt/clean_spree,APohio/spree,Nevensoft/spree,Nevensoft/spree,jordan-brough/solidus,rbngzlv/spree,xuewenfei/solidus,miyazawatomoka/spree,jspizziri/spree,hifly/spree,calvinl/spree,zaeznet/spree,tomash/spree,CJMrozek/spree,TimurTarasenko/spree,jordan-brough/solidus,beni55/spree,locomotivapro/spree,bjornlinder/Spree,bricesanchez/spree,net2b/spree,alepore/spree,abhishekjain16/spree,useiichi/spree,knuepwebdev/FloatTubeRodHolders,calvinl/spree,yiqing95/spree,groundctrl/spree,vinayvinsol/spree,athal7/solidus,builtbybuffalo/spree,azranel/spree,vmatekole/spree,jimblesm/spree,tancnle/spree,adaddeo/spree,rbngzlv/spree,devilcoders/solidus,athal7/solidus,brchristian/spree,yomishra/pce,athal7/solidus,shekibobo/spree,rakibulislam/spree,Ropeney/spree,vcavallo/spree,siddharth28/spree,cutefrank/spree,azclick/spree,lsirivong/spree,siddharth28/spree,lyzxsc/spree,omarsar/spree,NerdsvilleCEO/spree,CiscoCloud/spree,omarsar/spree,jspizziri/spree,jspizziri/spree,fahidnasir/spree,tancnle/spree,zaeznet/spree,beni55/spree,lsirivong/solidus,Migweld/spree,joanblake/spree,adaddeo/spree,Hawaiideveloper/shoppingcart,woboinc/spree,kitwalker12/spree,derekluo/spree,DarkoP/spree,wolfieorama/spree,jaspreet21anand/spree,yiqing95/spree,azranel/spree,CJMrozek/spree,piousbox/spree,wolfieorama/spree,tomash/spree,gregoryrikson/spree-sample,CiscoCloud/spree,Senjai/solidus,alejandromangione/spree,adaddeo/spree,pulkit21/spree,karlitxo/spree,miyazawatomoka/spree,tomash/spree,odk211/spree,Kagetsuki/spree,gautamsawhney/spree,yushine/spree,Boomkat/spree,ramkumar-kr/spree,ramkumar-kr/spree,gregoryrikson/spree-sample,firman/spree,ahmetabdi/spree,orenf/spree,azclick/spree,groundctrl/spree,hoanghiep90/spree,piousbox/spree,scottcrawford03/solidus,kewaunited/spree,kewaunited/spree,tesserakt/clean_spree,CiscoCloud/spree,yomishra/pce,pervino/spree,jasonfb/spree,beni55/spree,hifly/spree,shaywood2/spree,project-eutopia/spree,Mayvenn/spree,volpejoaquin/spree,raow/spree,Lostmyname/spree,rakibulislam/spree,StemboltHQ/spree,shioyama/spree,firman/spree,yiqing95/spree,pulkit21/spree,sfcgeorge/spree,ujai/spree,Senjai/spree,forkata/solidus,caiqinghua/spree,jaspreet21anand/spree,Boomkat/spree,vinsol/spree,vulk/spree,progsri/spree,DynamoMTL/spree,Ropeney/spree,TimurTarasenko/spree,alvinjean/spree,miyazawatomoka/spree,calvinl/spree,agient/agientstorefront,jordan-brough/solidus,sliaquat/spree,shaywood2/spree,vulk/spree,TimurTarasenko/spree,maybii/spree,softr8/spree,grzlus/spree,jhawthorn/spree,robodisco/spree,PhoenixTeam/spree_phoenix,bricesanchez/spree,radarseesradar/spree,vcavallo/spree,keatonrow/spree,edgward/spree,imella/spree,patdec/spree,Senjai/solidus,ujai/spree,kewaunited/spree,SadTreeFriends/spree,berkes/spree,watg/spree,keatonrow/spree,lsirivong/solidus,sideci-sample/sideci-sample-spree,welitonfreitas/spree,PhoenixTeam/spree_phoenix,ayb/spree,lsirivong/solidus,FadliKun/spree,orenf/spree,KMikhaylovCTG/spree,robodisco/spree,gautamsawhney/spree,knuepwebdev/FloatTubeRodHolders,reidblomquist/spree,sunny2601/spree,bonobos/solidus,pervino/solidus,keatonrow/spree,edgward/spree,urimikhli/spree,volpejoaquin/spree,TrialGuides/spree,xuewenfei/solidus,Lostmyname/spree,vcavallo/spree,SadTreeFriends/spree,LBRapid/spree,jparr/spree,CiscoCloud/spree,derekluo/spree,locomotivapro/spree,camelmasa/spree,Senjai/solidus,vinayvinsol/spree,lyzxsc/spree,woboinc/spree,sliaquat/spree,berkes/spree,brchristian/spree,bricesanchez/spree,JuandGirald/spree,tailic/spree,jhawthorn/spree,DarkoP/spree,Migweld/spree,Senjai/spree,hoanghiep90/spree,urimikhli/spree,biagidp/spree,edgward/spree,dotandbo/spree,shaywood2/spree,grzlus/solidus,lyzxsc/spree,yomishra/pce,pervino/spree,tancnle/spree,njerrywerry/spree,Machpowersystems/spree_mach,Boomkat/spree,jparr/spree,quentinuys/spree,jimblesm/spree,radarseesradar/spree,jordan-brough/solidus,tomash/spree,imella/spree,berkes/spree,devilcoders/solidus,softr8/spree,hifly/spree,freerunningtech/spree,carlesjove/spree,jhawthorn/spree,degica/spree,carlesjove/spree,FadliKun/spree,caiqinghua/spree,progsri/spree,delphsoft/spree-store-ballchair,brchristian/spree,volpejoaquin/spree,derekluo/spree,NerdsvilleCEO/spree,ahmetabdi/spree,LBRapid/spree,priyank-gupta/spree,forkata/solidus,kitwalker12/spree,karlitxo/spree,NerdsvilleCEO/spree,joanblake/spree,CJMrozek/spree,ckk-scratch/solidus,yushine/spree,mleglise/spree,odk211/spree,Mayvenn/spree,dandanwei/spree,pervino/solidus,thogg4/spree,Ropeney/spree,dafontaine/spree,vinsol/spree,thogg4/spree,sfcgeorge/spree,zamiang/spree,dotandbo/spree,Ropeney/spree,grzlus/solidus,jparr/spree,PhoenixTeam/spree_phoenix,piousbox/spree,camelmasa/spree,groundctrl/spree,priyank-gupta/spree,ramkumar-kr/spree,tailic/spree,quentinuys/spree,welitonfreitas/spree,sliaquat/spree,trigrass2/spree,jordan-brough/spree,knuepwebdev/FloatTubeRodHolders,delphsoft/spree-store-ballchair,edgward/spree,mindvolt/spree,yiqing95/spree,DynamoMTL/spree,njerrywerry/spree,AgilTec/spree,jeffboulet/spree,KMikhaylovCTG/spree,watg/spree,derekluo/spree,RatioClothing/spree,pervino/spree,calvinl/spree,fahidnasir/spree,priyank-gupta/spree,vmatekole/spree,richardnuno/solidus,adaddeo/spree,zamiang/spree,jordan-brough/spree,Arpsara/solidus,madetech/spree,urimikhli/spree,alejandromangione/spree,xuewenfei/solidus,Kagetsuki/spree,forkata/solidus,archSeer/spree,agient/agientstorefront,madetech/spree,robodisco/spree,jeffboulet/spree,patdec/spree,orenf/spree,athal7/solidus,nooysters/spree,keatonrow/spree,reidblomquist/spree,Mayvenn/spree,grzlus/solidus,SadTreeFriends/spree,DarkoP/spree,patdec/spree,jordan-brough/spree,JDutil/spree,pulkit21/spree,Kagetsuki/spree,bjornlinder/Spree,radarseesradar/spree,surfdome/spree,tailic/spree,njerrywerry/spree,dafontaine/spree,StemboltHQ/spree,firman/spree,rbngzlv/spree,gautamsawhney/spree,radarseesradar/spree,net2b/spree,NerdsvilleCEO/spree,reinaris/spree,StemboltHQ/spree,builtbybuffalo/spree,abhishekjain16/spree,freerunningtech/spree,AgilTec/spree,shekibobo/spree,bonobos/solidus,Hates/spree,Engeltj/spree,abhishekjain16/spree,jparr/spree,fahidnasir/spree,assembledbrands/spree,trigrass2/spree,builtbybuffalo/spree,patdec/spree,vmatekole/spree,lsirivong/spree,freerunningtech/spree,jasonfb/spree,KMikhaylovCTG/spree,JDutil/spree,JDutil/spree,useiichi/spree,quentinuys/spree,alejandromangione/spree,rbngzlv/spree,Hawaiideveloper/shoppingcart,azranel/spree,Hates/spree,biagidp/spree,Migweld/spree