Create separate reranking feature class for original ranking score
Allow negative values when binning logarithmically in reranking
Separate out types-in-common, model-compare rerank features, remove 'combined' feature spec
Pretty-print features when '--debug features'
Don't use index 0 for Trove memoizers, stands for missing entry
Reranker: Fix handling of NaN/+Inf/-Inf, use ! not $ for bin distinctiveness
Reranker: Don't tag combined features by default, split '--debug combined-features' into 'tag-...', 'show-...'
Reranker: Eliminate extra memoization step, fix intercept handling
Add --rerank-binning for controlling whether binned and/or non-binned features appear