Have rubocop ignore the Gemfile
Have rubocop ignore the Gemfile

Signed-off-by: Dennis Ideler <2ccb600f3f8bbe9c4900f0371448c2a6e1289ec6@fundingcircle.com>

iainbeeston/shipment_tracker,FundingCircle/shipment_tracker,FundingCircle/shipment_tracker,FundingCircle/shipment_tracker,FundingCircle/shipment_tracker,iainbeeston/shipment_tracker,iainbeeston/shipment_tracker,iainbeeston/shipment_tracker