Added some notes on calculator refacator.
Added some notes on calculator refacator.

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