Eloquence revived

Fixes a Lua error in raids.

Modern clients hand addons "secret" values in some content — data an addon may receive but not read. Eloquence's race lookup tried to use one as a lookup key during a raid roster scan, which raised an error on boss kills.

The visible error was harmless in itself. The same weakness existed in the code that runs for every chat message, though, where a secret name would have dropped the message from your chat frame instead of just leaving it undialected. Both are fixed: unreadable names are now skipped quietly, and the speaker's race still resolves through their GUID as normal.

/elo doctor reports how often this happens, if you're curious.