Per-protocol content IDs

[TheElectronWill]

Each protocol (including different versions of the protocol of the same game) can provide its own ids for the game content.
Each protocol should have two maps

Map[protocol id -> internal id]: Index[Int]
Map[internal id -> protocol id]: Index[Int]

That are constructed from the protocol's data, which maps type names (universal) to protocol ids (specific to one protocol).

val config: TomlConfig = // config that maps typenames to protocol ids
for((typename, protocolId) <- config) {
    val i= TuubesRegistry(typename).internalId
    map1 += (i, protocolId)
    map2 += (protocolId, i)
}

This is a part of #17.