New workload type: DATAGEN

[AndyGrant]

The GenFens interface is finished in Torch. The result is that public engines can be executed like follows, to generate openings: ./Ethereal "genfens N seed S book <?book|None>". Private engines can be run via ./Torch "setoption name EvalFile value ..." "genfens N seed S book <?book|None". In both cases, the OpenBench client will expect N lines of output starting with "info string genfens ".

The following steps will finalize this process:

• Add a new workload type to the workload creation page called DATAGEN.
• In most cases, treat these exactly the same as GAMES workloads. Consider using Enum
• However, use the trinomial modeling and not the pentanomial modeling
• In the client, remove the -repeat argument to Cutechess
• Add a utility to execute many copies of the engine at once, to run genfens, and collect them.

[AndyGrant]

Resolved a while ago, but no existing demonstration in a public engine is present.