Webjournal: Improve the Indico seminars widget

* Improves the Indico seminars widget but fetching more carefully
  information about the creator/chair of the event as well as the
  URL.

(closes #1980)

Signed-off-by: Nikolaos Kasioumis nikolaos.kasioumis@cern.ch
Merge pull request #50 from kasioumis/prod-master-webjournal-widget-seminars-improve-xml-parsing

Webjournal: Improve the Indico seminars widget