Bug: Adding talks to personal schedule more than once

[Tina Müller]

Hi,

We are trying to sort out which talks are the most interesting ones,
so before approving them, the talks_amin members can add them to
their personal schedule.

The problem: for unapproved talks the user name is added to the
talk, but you can do this multiple times, and the name is added
for every click.

For those who have access to the database, this is one of the
talks:
http://act.yapc.eu/gpw2013/talk/4420

Maybe someone can remove the duplicates, and I tell our orga members
to take care and not click multiple times?

thanks,
tina