General overhaul

See merge request teichman/ebpfcat!1

fully untested, though

useful for testing stuff

we can do without.

this is not well tested, though

and warn about abuse of if statement

until we find a good way to test those

let's see if that works...

this actually also fixes a subprograms bug

they can already have ArrayMaps, but not much more

This is generally a good idea as the packet usually needs to be
addressed a lot and should not be overwritten by function calls.

this is not thoroughly tested.