Allow to use a genus or higher taxon ranks

[damianooldoni]

Providing a genus among the "list of species" will stop the instance to work correctly if occurrences are found linked to a species (or subspecies, form, ...) belonging to that genus.

Example: the LIFE RIPARIAS instance stopped working on Dec 22 as one of the new species added on Dec 21 was a genus (Carpobrotus) and one downloaded occurrence (occurrenceID: 4170944384) was linked to the species Carpobrotus N.E.Br.. Thanks @niconoe for finding the core of the problem I have described here. Feel free to add more details if needed.

Probably we should allow not only genera, but also higher taxon ranks up to classes.