reset title variable when looping with biblio A/T

reset title variable when looping with biblio A/T

Two templates that I'm concerned with, though there may be others that could use
this treatment: biblio.record_entry.email and biblio.record_entry.print

Basically, they can group events from the same user and consolidate bibs, but as
they loop through the bibs they're not clearing the temporary variable that
contains the bib title, so we get duplicated and run-on titles in the output.

Signed-off-by: Jason Etheridge <jason@esilibrary.com>