Refactored transport layer code for adding terms

django/website/chn_spreadsheet/importer.py

django/website/hid/tabs/view_and_edit_table.py

django/website/hid/tests/add_edit_item_view_tests.py

django/website/hid/tests/categorize_items_tests.py

django/website/hid/tests/views_tests.py

django/website/hid/views/item.py

django/website/transport/items.py

django/website/transport/tests/free_tagging_tests.py

django/website/transport/tests/item_add_term_tests.py

django/website/transport/tests/item_delete_all_term_tests.py

.../website/transport/tests/taxonomy_term_itemcount_tests.py