extract auto_handle to new canvas_uuid gem

Change-Id: Ic226e61e900532cc3acf08444b316b6e2bb6b368
Reviewed-on: https://gerrit.instructure.com/30049
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: Simon Williams <simon@instructure.com>
QA-Review: Caleb Guanzon <cguanzon@instructure.com>
Product-Review: Simon Williams <simon@instructure.com>