new
 * mass addition of taxon constraints
 * NTs: glandular system, non-connected functional system (from AEO)
 * NT: lymph heart
 * split cement gland into distinct barnacle and mollusc terms
 * added grouping 'arcuate ligament' class, plus new subtypes
 * added grouping class 'nasal meatus', plus new subtypes
 * Strengthening taxon constraints
 * layer of skin broadened to layer of integumentary system
 * 'spidermis' is now generic, 'skin epidermis' is now vert structure
 * neural crest broadened to craniates to avoid potential hagfish forebrain issue
 * NTs: now have all 4 ostia of heart
 * Removed incorrect syn for entepicondyle. Fixes issue #405 reported by AD