loongson/pypi: links for pttwebcrawler

loongson/mirror PttWebCrawler-1.8.tar.gz
loongson/mirror PttWebCrawler-1.7.tar.gz
loongson/mirror PttWebCrawler-1.6.tar.gz
loongson/mirror PttWebCrawler-1.5.tar.gz
loongson/mirror PttWebCrawler-1.4.tar.gz