LuaEntity::backer_name Spidertron support

[LuziferSenpai]

Hey,

it would be awesome if we could read and write the name of the spidertron via the backer_name function!

Greetz,

Luzifer

[robot256]

Looks like this is a duplicate and has been implemented, per viewtopic.php?p=532006#p532006

(Found this when looking to see if the original post had been updated, thanks devs!)