Optimize historyofvaccines.theme file for speed

[mtedeschi]

@jmaj: It looks like the speed issues are related to loading so much stuff on the theme. If you clear out that file, it reduces the load time significantly—of course, because its not needing to load so much. I think we should rework this so we only show particular things when necessary (for instance, we only need the exposed form controls for the gallery on /gallery and the media-item content type.

[jmaj]

Alright, so hopefully after the optimizations the site feels a bit faster than before