Sem Cache

De http://stackoverflow.com/questions/49547/making-sure-a-web-page-is-not-cached-across-all-browsers/2068407#2068407 ..

response.headers["Cache-Control"] = "no-cache, no-store, must-revalidate" // HTTP 1.1.
response.headers["Pragma"] = "no-cache" // HTTP 1.0.
response.headers["Expires"] = "0" // Proxies.