Remove RestrictedPaths check

This check doesn't belong in Overcommit, and should instead be moved to
the individual repository that needs it, as is specific to a Rails
application, and Overcommit should not be specific to Rails apps.

Change-Id: I31b61910e061e4da0454ce72451f5b7dad8bdf99
Reviewed-on: https://gerrit.causes.com/30850
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Greg Hurrell <greg@causes.com>
Cut version 0.4.1

Change-Id: I6da585539c0668850b609f89f6db045fc0981cfc
Reviewed-on: https://gerrit.causes.com/30851
Tested-by: jenkins <jenkins@causes.com>
Reviewed-by: Greg Hurrell <greg@causes.com>