feat: add watcher to Autoplay Prop (SSENSE#344)

* fix(carousel): flush the slides left when they don't fill the width (SSENSE#323)

* fix(carousel): Flush the slides left when they don't fill the width (SSENSE#323)

When there are too few slides to fill the row, with scrollPerPage, the slides were flushed right instead of left.
By bounding maxOffest to a minimum of 0, the slides are aligned on the left-hand-side

Fix SSENSE#323

* style(play): Use capitals in tests for consistency

* v0.16.1

* chore: build

* feat(standard): watch autoplay prop and enable/disable autoplay