Change "ruler" to "name" and "ruler_detail" to "name_detail"

[vbalalian]

Incorporating Roman Republican coinage makes the field name "ruler" unsuitable; "name" would be more appropriate. This change will require comprehensive replacement of the field name in web_scraper.py, main.py, test_web_scraper.py, and test_api.py, as well as test_coins.json.