loongson/pypi: links for beets-artistcountry

loongson/mirror beets-artistcountry-0.3.0.tar.gz
loongson/mirror beets-artistcountry-0.2.0.tar.gz
loongson/mirror beets_artistcountry-0.2.0-py2.py3-none-any.whl
loongson/mirror beets-artistcountry-0.1.2.tar.gz
loongson/mirror beets_artistcountry-0.1.2-py2.py3-none-any.whl
loongson/mirror beets-artistcountry-0.1.1.tar.gz
loongson/mirror beets-artistcountry-0.1.tar.gz