refactor respond_with engines hash build into single method
refactor respond_with engines hash build into single method

mwpastore/sinatra,JonMidhir/sinatra,JonMidhir/sinatra,burningTyger/sinatra,burningTyger/sinatra,mwpastore/sinatra,jkowens/sinatra,JonMidhir/sinatra,sinatra/sinatra,jkowens/sinatra,burningTyger/sinatra,jkowens/sinatra,ryanshaw/sinatra,ryanshaw/sinatra,mwpastore/sinatra,sinatra/sinatra