Reduce Memory usage with linked files

Right now we have a big memory problem in Blender when we load scenes with many large linked blend-files.

We have a master scene where many complex single blend-files (about 300mb) are linked. In the master scene all linked files are not visible by default. Nevertheless, when loading the master file, all linked Blender files are loaded into memory.

Our suggestion here would be to load only visible linked scenes into memory and to unload them again when hiding. Alternatively it would be good to be able to switch not only the visibility but also the loading.