Accept absolute URI scheme as uppercase
Accept absolute URI scheme as uppercase

We should be doing a case insensitive comparison to be correct,
but this is more expensive. Almost all clients send lowercase,
this patch fixes handling of the aws/aws-sdk-php client which
sends uppercase, and no known client sends mixed case so I am
holding back on the more expensive solution for the moment.

cad627/cowboy,pap/cowboy,turtleDeng/cowboy,yangchengjian/cowboy,callsign-core/cowboy_hybi00,276361270/cowboy,bobos/ecweb,nviennot/cowboy,cad627/cowboy,grahamrhay/cowboy,kivra/cowboy,rabbitmq/cowboy,hairyhum/cowboy,sile/cowboy,omusico/cowboy,binarin/cowboy,binarin/cowboy,dangjun625/cowboy,yangchengjian/cowboy,paulperegud/cowboy,ninenines/cowboy,bsmr-erlang/cowboy,acrispin/cowboy,odo/cowboy,CrankWheel/cowboy,Reimerei/cowboy,noname007/cowboy,K2InformaticsGmbH/cowboy,callsign-core/cowboy_hybi00,imdeps/cowboy