Access to wire friend list through e2

[Isemenuk27]

will be useful for single chip contraptions

[Denneisk]

This is relatively trivial, this just needs to be exposed.

Looking ahead, friendslists are very wasteful.
https://github.com/wiremod/wire/blob/master/lua/wire/stools/friendslist.lua#L56-L66
https://github.com/wiremod/wire/blob/master/lua/entities/gmod_wire_friendslist.lua#L50-L56
The server should do these calculations once and then propagate them to every chip.