Send cloud maps through salt renderer system

Fixes #8403.

Also, this changes some (undocumented) usage; previously, if mako was detected, it would always be used as the rendering engine. If mako is already defined as the default renderer, this change will not break anything. However, if mako was previously used for cloud maps, and no render pipes are set inside the map (because, why would they be?), and the default renderer is not set to mako, there will be breakage.

Do NOT backport this fix; let's leave it in develop until the Lithium release, so that affected people have time to get used to it.

Ping @inthecloud247.