Add Librivox audio books

[mapmeld]

I just returned from a volunteer trip to schools using IIAB. As described in #93, I'm adding 3 issues

Librivox is a volunteer effort to make public domain audio recordings in multiple languages from public domain books. In 2010-2011, I found several stories to share with students in Uganda and Haiti. Audiobooks assist language learners and new readers. They also make it easy for one teacher with a computer to share and discuss a book with many students.

Adding a new category of content to IIAB is likely a larger effort than my other two issues. I'm a web developer and would be happy to research this further if there is interest

[paperdigits]

@mapmeld does librevox have an easy place to download the files in bulk? Looks like their hosted on archive.org.

[tomhiggins]

New to this project so please forgive me if this has been covered already.

You can start at https://archive.org/details/librivoxaudio&tab=collection and scrap from that.

A while back I tossed together a script to help me in gettings whole collections from archive.org https://github.com/tomhiggins/ArchiveOrgCollectionGrabber

Hope that helps some.
-tom