Fix Staging Order on Subassemblies

[tstehler1]

This is a tiny little pet peeve that annoys the [redacted] out of me.

When I'm building my rockets, I use the same launch core for almost everything. Therefore, with the new update and all its lovely features, I created it and saved it as a subassembly. However, this is almost equally as tedious as building the darn thing over and over. When I stick the launch core onto my rocket, it puts the core's engines into stages 0,1, and 2... Directly overlapping whatever I have already built. I then have to add more stages and redo the entire order of the engines, which was half the work of building the darn thing.

Is there a fix for this? If not, I think it should be included in an update in the future.

*Places two cents on table*