This is enabled for title and description only, because that's usually
what we put on "external" documents such as invoices.

By "resource" here it means products, services, components and their
individual variations

In short, change the translation configuration from 
![Screenshot_2017-12-05_at_10.22.39](/uploads/2c72a0b35dbbde1ec6d7156f2e2f372a/Screenshot_2017-12-05_at_10.22.39.png)

to 

![Screenshot_2017-12-05_at_10.23.31](/uploads/d86c2fce6a9d134e17b5fddc983491a3/Screenshot_2017-12-05_at_10.23.31.png)


/reviewed-on nexedi/erp5!515