Update README instructions
Update README instructions

akorchaginn/Sylius-Standard,Sylius/Sylius-Standard,Sylius/Sylius-Standard,Sylius/Sylius-Standard,akorchaginn/Sylius-Standard,lchrusciel/Sylius-Standard,akorchaginn/Sylius-Standard,lchrusciel/Sylius-Standard,lchrusciel/Sylius-Standard,lchrusciel/Sylius-Standard