proxy: Force all SSL certificates to be trusted
proxy: Force all SSL certificates to be trusted

By setting the CA file we make it a certificate error if the certificate
is self-signed.

Fixes: https://bugzilla.gnome.org/show_bug.cgi?id=663783

ThomasBollmeier/librest-oauth-proxy,ThomasBollmeier/librest-oauth-proxy,GNOME/librest,Distrotech/librest,Distrotech/librest,GNOME/librest,GNOME/librest