remove some rails 2 vestigials

Change-Id: Ic6bf038c47e95430b0a96954ab84ff0a96333a88
Reviewed-on: https://gerrit.instructure.com/38964
Tested-by: Jenkins <jenkins@instructure.com>
Reviewed-by: James Williams  <jamesw@instructure.com>
Product-Review: Cody Cutrer <cody@instructure.com>
QA-Review: Cody Cutrer <cody@instructure.com>