merge same file_reference

[EzimetYusup]

Hi @simonwagner, first of all great repo, I was wondering how mergepbx handle the cases such as: my colleague added file a.swift to a group, at the same time I also added a.swift to the same group, when we merge our stuff, we will get merge conflict, same file_reference but different uuid, currently what I am seeing when I use mergepbx as merge tool is the merge conflict was resolved but in the group there are two a.swift file. I though mergepbx would only choose one of the file_reference from merge conflict. thanks!