Updated translation.rst
Updated translation.rst

I think that we should mention that clearing the cache is required in order to see the new translations appear.
Sylius/Sylius,lchrusciel/Sylius,pamil/Sylius,diimpp/Sylius,SyliusBot/Sylius,loic425/Sylius,GSadee/Sylius,loic425/Sylius,Zales0123/Sylius,diimpp/Sylius,kayue/Sylius,kayue/Sylius,antonioperic/Sylius,kayue/Sylius,Zales0123/Sylius,101medialab/Sylius,Arminek/Sylius,Sylius/Sylius,SyliusBot/Sylius,pamil/Sylius,101medialab/Sylius,pamil/Sylius,antonioperic/Sylius,loic425/Sylius,antonioperic/Sylius,Sylius/Sylius,Zales0123/Sylius,diimpp/Sylius,101medialab/Sylius,Arminek/Sylius,GSadee/Sylius,Arminek/Sylius,GSadee/Sylius,SyliusBot/Sylius,lchrusciel/Sylius,lchrusciel/Sylius