display files and folders alphabetically in the document browser

[porres]

this is an issue for the live electronics tutorial, I made it so that folders and patch files are in alphabetical order but the browser prioritizes folders over files, which screws up the order

for instance, in Waveshaping, 7 and 8 come before 1 and 2

[dromer]

Some filebrowsers have an explicit view option like "Mingle Files and Folders" (pcmanfm).
Should this be an advanced option in the settings perhaps?

Most filebrowsers will not do this automatically and I would intuitively expect folders and files to be grouped separately in these listings. I do see the use when the naming is meant to sort the entire contents disregarding the type.
An explicit setting for this behavior would be better than outright changing it.