* track usage of older feature steps

* remove typo whitespace

* make buildvars consistently cased

V 147

Update readme

update changelog

Document tests

Test updates

Update to reflect Hatchet updates

V 145

Due to how the version checks work - via sorting, not actual comparison - this previously resulted in _always_ installing sqlite3, even though it was already bundled for lower versions of python. The second version check also encompasses 3.7.0+, so there is no need to respecify the check.