Bastien Montagne
d1f96f9b11
It's not always possible to keep 'by hand' parent relationships valid in collections hierarchy. Add functions to remake those (re-using/factorizing code from `readfile.c` `lib_link_collection_data()` function). Can't stress again how painful it is to have those kind of backward relationships in our data structures, those *always* end up being serious issues to keep in sync... Should only be generated on the fly when needed, period. :(