* BaseFragmentBuilder now quotes table and col names for joins
* Refactored libsq.engine so that the SQL generated from SLQ input can be tested
* Deleted dead code; additional comments
* 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