update umi config by setting polyfill to IE11 and enable dynamicImport

.gitignore

@@ -28,11 +28,11 @@ jsconfig.json
 *.log
 
 functions/mock
-.temp/**
+.temp
 
 # umi
 .umi
 .umi-production
 
 # screenshot
-screenshot
+screenshot

config/config.js

@@ -17,7 +17,8 @@ export default {
           default: 'zh-CN', // default zh-CN
           baseNavigator: true, // default true, when it is true, will use `navigator.language` overwrite default
         },
-        polyfills: ['ie9'],
+        dynamicImport: true,
+        polyfills: ['ie11'],
         ...(!process.env.TEST && require('os').platform() === 'darwin'
           ? {
               dll: ['dva', 'dva/router', 'dva/saga', 'dva/fetch'],