libapache2-mod-proxy-uwsgi doesn't specify mod-proxy as a requirement

libapache2-mod-proxy-uwsgi depends on mod-proxy being loaded, otherwise it fill refuse to load and stop the server from starting. However just doing "a2enmod proxy_uwsgi" does not also enable mod proxy. See also the related bug on Debian: https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=785610

The fix would be to add "# Depends: proxy" to /etc/apache2/mods-available/proxy_uwsgi.load (as it is in /etc/apache2/mods-available/proxy_ajp.load for example)