adding zines from other LT libraries

[sparky]

Hello! Thought we should get the ball rolling a bit. I talked a bit
with Sonya about this already, but think it's a pretty integral to
zining via LT and it will probably come up for everyone at some point:
I realized you can't add zines from other people's accounts unless
they have isbns! So for most zines this ain't happenin'. This means
you have to manually add each zine, putting zine catalogers at a sharp
disadvantage compared to book catalogers! As a concern this has been
addressed and will be looked into. Exciting!