Fixes possible ConcurrentModificationException in State#getSimpleValues when the process of converting to a simple value causes #put.
Fixes possible ConcurrentModificationException in State#getSimpleValues when the process of converting to a simple value causes #put try 2.
Fixes ReferentialText#toPublishes sometimes removing an element by itself that looks like a paragraph if there weren’t any accompanying text.
Merge branch 'release/2.3'