The current way table structure metrics are computed does not cover
cases when none table is found and all stats are empty.
This PR fixes this + adds some hardenning tests for table eval
processor.
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Co-authored-by: Yao You <theyaoyou@gmail.com>
- add helper to run inference over an image or pdf of table and compare
it against a ground truth csv file
- this metric generates a similarity score between 1 and 0, where 1 is
perfect match and 0 is no match at all
- add example docs for testing
- NOTE: this metric is only relevant to table structure detection.
Therefore the input should be just the table area in an image/pdf file;
we are not evaluating table element detection in this metric
