Merge pull request #396 from ahilles107/improve_slideshows

Improve slideshows in templates
publication override by request param fix
Merge pull request #399 from takeit/publication_override

publication override by request param fix
Merge branch 'master' of github.com:ahilles107/Newscoop
Merge branch 'master' of github.com:ahilles107/Newscoop
new installer