* Expose source.Set.Data() method
* jsonw.writeJSON cleaned up
* sq add now respects --json
* Location strings are subject to more scrutiny
* Ignore .db files in project dir
* sq add is more restrictive about location string
* source.RedactedLocation now uses 'xxxxx' per stdlib url.URL.Redacted()
* Update changelog for v0.23.0
* typos
* Type Detector refactor
* json driver impl; refactoring of source.Files reader et al
* working on kind detector
* significant switcheroo of packages
* partway throught refactoring Kind
* major package switcheroo for Kind
* initial refactoring for the numRows param
* work on driver.NewBatchInsert
* work on NewBatchInsert
* batch insert seems to work
* switched testh.Insert to use BatchInsert
* doc cleanup
* batch insert for dbwriter and csv
* removed unneeded NumRows from driver.StmtExecer
* minor tidyup
