Translations in one file

[feho1]

Hi everyone, i tried searching forum and google but could not find answer.
I want to translate my shop but do i have to go to themes, modules and etc in back office one by one for every language? 
Can i translate every thing in one file ?
I want to have one file for every translation like prestashop offers for every module in translations folder but in one file is this possible?
Or can i have all the translations in one folder for every translations there is without going to back office? because prestashop offers only for modules not the theme.

Or any other way to be able to translate the whole shop from one language to another ?

Thanks in advance.