Incertae sedis classification to a rank other than domain

[lmrodriguezr]

If a name is declared as incertae sedis, it currently cannot be assigned to ranks other than domains. We should support assigning names to ranks not immediately above the name's rank when declaring incertae sedis.

[vangberg]

Todo:

• Remove legacy Name#incertae_sedis and Name#incertae_sedis_text
• Ensure incertae sedis placement works with batch upload