Name `verify_*` functions

[cynthiahqy]

Overall pattern is verify_<object>_<element filter>_property

Verifying pairwise or link properties:

• verify_named_all_pairs_1to1()
• verify_named_all_pairs_unique()

Verifying name or value sets:

• verify_named_all_names_unique()
• verify_named_match_names_exact() / _contain / _within

[cynthiahqy]

_pairs is too long, removed

[cynthiahqy]

resolved in #121