[Evals] More OOTB metrics in genkitEvals

[ssbushi]

Is your feature request related to a problem? Please describe.
Current metrics in genkitEvals are very RAG focused and hinder users with basic use-cases from starting to use evaluations.

Describe the solution you'd like
Provide more evaluators out of the box that are not specific to RAG (e.g., exactMatch, criteria-based, etc). Some mix of evaluators that use "reference" and "output" would be ideal.

Additional context
#1603 (comment)