ability to avoid wormholes by signature

[Jambe]

Often one wants to avoid the current shortest route to check the healthy/viability of alternative routes.

Currently the only ways to do this are workaround-ish:

1. avoid the system that contains a wormhole in the route you want to avoid
2. if it's unavoidable (e.g. a pipe system or if there are two+ holes in a J-Space system and you want to avoid one)
   • change the hole you want to avoid to EOL in TW then avoid EOLs in SC (or temporarily delete the hole in TW)

It would be very useful if we could make SC avoid wormholes by their signatures (ABC-123).