Files in public/ folder should not be requested through proxy (facebook#2326)

Author: gaearon

scripts/start.js

@@ -66,7 +66,7 @@ choosePort(HOST, DEFAULT_PORT)
     const compiler = createCompiler(webpack, config, appName, urls, useYarn);
     // Load proxy config
     const proxySetting = require(paths.appPackageJson).proxy;
-    const proxyConfig = prepareProxy(proxySetting);
+    const proxyConfig = prepareProxy(proxySetting, paths.appPublic);
     // Serve webpack assets generated by the compiler over a web sever.
     const serverConfig = createDevServerConfig(
       proxyConfig,