some fun SubProxy

[Leopold Toetsch]

I have put together a (currently dynamic) class SubProxy, which takes a 
filename and sublabel. On first invoke the file source gets loaded:

_main:  null P1
        load_pmc "subproxy", P1
        new P3, .Key
        set P3, "ext.imc"     # file
        new P4, .Key    
        set P4, "_ext_main"   # sub label
        push P3, P4
        new P0, .SubProxy
        assign P0, P3
        invokecc
        print "back\n"
        invokecc
        print "back\n"
        end
Works fine.
Should I put that in dynclasses or core classes?
leo