point out that the example is a config.ru in the README, fixes #313
point out that the example is a config.ru in the README, fixes #313

kgrz/sinatra,davydovanton/sinatra,trexnix/sinatra,ABaldwinHunter/sinatra-classic,twanies/sinatra,emiliocorpus/sinatra,jkowens/sinatra,nju520/sinatra,wzheng1/sinatra,jenalgit/sinatra,Wirachmat/sinatra,bmizerany/sinatra,siberianbear/sinatra,sinatra/sinatra,defsprite/sinatra,gferguson-gd/sinatra,lastcat/sinatra,eileencodes/sinatra,d-bot/sinatra,ksw2599/sinatra,mwpastore/sinatra,jkowens/sinatra,mwpastore/sinatra,ABaldwinHunter/sinatra-classic,gferguson-gd/sinatra,kyontan/sinatra,davydovanton/sinatra,QLGu/sinatra,eileencodes/sinatra,ryanshaw/sinatra,guidohcosta/sinatra,ktw1222/sinatra,trexnix/sinatra,ganmacs/sinatra,RosenDimov/sinatra,Callygraphy/morrissey,ganmacs/sinatra,twanies/sinatra,miyazawatomoka/sinatra,lastcat/sinatra,guidohcosta/sinatra,howtolearntocode/sinatra,RosenDimov/sinatra,marocchino/sinatra,jenalgit/sinatra,autopp/sinatra,ktw1222/sinatra,sethuster/sinatra,frechei/sinatra,siberianbear/sinatra,miyazawatomoka/sinatra,laplaceliu/sinatra,autopp/sinatra,defsprite/sinatra,sinatra/sinatra,DoraALin/sinatra,jkowens/sinatra,porras/sinatra,d-bot/sinatra,blambeau/sinatra,Rayheng/sinatra,frechei/sinatra,cyberid41/sinatra,kyontan/sinatra,midorineko/sinatra,burningTyger/sinatra,DoraALin/sinatra,laplaceliu/sinatra,emiliocorpus/sinatra,midorineko/sinatra,wzheng1/sinatra,nju520/sinatra,mwpastore/sinatra,QLGu/sinatra,burningTyger/sinatra,JonRowe/sinatra,ksw2599/sinatra,kumji/sinatra,cyberid41/sinatra,howtolearntocode/sinatra,sethuster/sinatra,JonMidhir/sinatra,burningTyger/sinatra,Wirachmat/sinatra,nicoayala/sinatra,dariubs/sinatra,JonRowe/sinatra,kumji/sinatra,JonMidhir/sinatra,Rayheng/sinatra,ryanshaw/sinatra,porras/sinatra,JonMidhir/sinatra,nicoayala/sinatra,dariubs/sinatra