Browser support

[superdweebie]

I've been tackling this over the past two days, and it isn't straightforward. The take home is that we have to give up the concept of a bso file. Rather than episode json and audio packed into the one bso file, we need two separate files. This means that the inital idea of being able to simply load the data for an episode when offline will not be so straightforward. :(

• ff only has partial support for mp3. If we want to support ff, then we need to supply audio in .ogg as well as mp3.
• chrome on android doesn't support playing audio from a blob, it has to be a separate file. There is a commited fix for this, but it will be 6-12 months before the commit is in most users browser (current version is 39, the commit isn't in 40, so it will be in version 41 or higher).

[superdweebie]

Ok. This is done. bso files are gone. Both ogg and mp3 are supported, so both ff and chrome are working.