Update docs

URLs changed http://www.pkware.com/support/zip-application-note https://www.pkware.com/support/zip-app-note

https://developer.mozilla.org/en/The_data_URL_scheme https://developer.mozilla.org/en-US/docs/Web/HTTP/data_URIs

APPNOTE.TXT changed https://pkware.cachefly.net/webdocs/casestudies/APPNOTE.TXT