ENYO-3683: make possible to show more than one line in pop-up's title

Related JIRA https://enyojs.atlassian.net/browse/ENYO-3683

Tested on W7, Chrome, FF, Opera, IE10.

Enyo-DCO-1.1-Signed-off-by: Olga Popova <olga.popova@hp.com>