Add HTTP_REFERER to env methods
Add HTTP_REFERER to env methods

appsignal/appsignal-ruby,matrinox/appsignal-ruby,stijnster/appsignal-ruby,stijnster/appsignal-ruby,q-m/appsignal,matrinox/appsignal-ruby,codefarmdev/haystack,subvisual/appsignal,appsignal/appsignal-ruby,appsignal/appsignal,matrinox/appsignal-ruby,rranelli/appsignal,stijnster/appsignal-ruby,appsignal/appsignal,appsignal/appsignal-ruby,appsignal/appsignal-ruby