CCN-15 addItem method added to lineitem helper
CCN-15 addItem method added to lineitem helper

crhistianr/angular-buyer,ordercloud-api/angular-buyer,crhistianr/angular-buyer,ordercloud-api/angular-seller,BrightMahi/aacBuyerNew,etundra-bsmith/angular-buyer,etundra-bsmith/angular-buyer,spencerwalker/angular-buyer,Four51SteveDavis/JohnsonBros,Four51SteveDavis/JohnsonBros,Four51SteveDavis/BevMediaPrototype,ordercloud-api/angular-seller,spencerwalker/angular-buyer,ordercloud-api/angular-admin,ordercloud-api/angular-admin,Four51/demo_buyer,BrightMahi/aacBuyerNew,Four51SteveDavis/BevMediaPrototype,ordercloud-api/angular-buyer,Four51/demo_buyer