v0.4.11: Assorted bugfixes, and new archive method: SingleFile!

We add a major new archive method in this release: SingleFile. On bare metal it requires installing Node and Chrome/Chromium, but it works out-of-the-box in the Docker version.

This finally allows ArchiveBox to pass all of the acid tests except one, and the archive for Github and many other sites are nicer than Wget was able to do on its own.