Find All References doesn't work for local variables

[Gurkenglas]

Replication: Visit https://github.com/tgstation/tgstation/blob/master/code/controllers/master.dm#L504 Ctrl-click queue_node_paused to go to its definition Alt-Shift-F12 in that to not find L504.

[SpaceManiac]

Looks like this isn't supported currently. The implementation is partway done. Local variable references are tracked in the "find all references" table, but local variables aren't looked up there.