Add a folder system to the craft loading/saving menu

I would really like to see the ability to make folders in the save/load craft menu. It's looks very cluttered when I have a bunch of crafts saved. For example:

Sat test 1
Sat test 2
Sat test 3
Sat test 4
Simple beast
Silly craft
Simple rocket
Simple cargo
X craft
Zebra rocket

It would look much nicer with folders (denoted with > in this example):

My crafts
Stat tests
Luna landers
Other
Default crafts

I don't know how easy it would be to add this, but I think it'd really be worth it.

Best, CodeCube