Bug 16587 - opac-sendbasket.pl is open to XSS

Bug 16587 - opac-sendbasket.pl is open to XSS

To test
1/ Hit a url like
http://localhost:8080/cgi-bin/koha/opac-sendbasket.pl?email_add=%3Cscript%3Ealert(%27XSS%27)%3C%2Fscript%3Ezz%40zz&comment=tes&bib_list=3

Where bib_list is a valid basket number
2/ Notice you get a javascript alert showing
3/ Apply patch
4/ Notice the text is now escaped

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>
Signed-off-by: Kyle M Hall <kyle@bywatersolutions.com>
Signed-off-by: Brendan Gallagher <brendan@bywatersolutions.com>