add npm import to vue-dynamic-import example

[rangermeier]

With v2.0.0-alpha.3 import of any NPM module can't be resolved and will show an error like the following.

This PR adds an import of momentjs to the vue-dynamic-import example to demonstrate this error, but I also was able to reproduce this with e.g. the es6-plain example.

WARNING in ./src/components/HelloWorld.vue?vue&type=script&lang=js&babel-target=modern (/home/ranger/workspace/webpack-babel-multi-target-plugin/node_modules/babel-loader/lib??ref--3!./node_modules/vue-loader/lib!./src/components/HelloWorld.vue?vue&type=script&lang=js&babel-target=modern) 16:19-25
    "export 'default' (imported as 'moment') was not found in 'moment'
        at HarmonyImportSpecifierDependency._getErrors (/home/ranger/workspace/webpack-babel-multi-target-plugin/node_modules/webpack/lib/dependencies/HarmonyImportSpecifierDependency.js:113:11)
        at HarmonyImportSpecifierDependency.getWarnings (/home/ranger/workspace/webpack-babel-multi-target-plugin/node_modules/webpack/lib/dependencies/HarmonyImportSpecifierDependency.js:60:15)
        at Compilation.reportDependencyErrorsAndWarnings (/home/ranger/workspace/webpack-babel-multi-target-plugin/node_modules/webpack/lib/Compilation.js:1326:24)
        at Compilation.finish (/home/ranger/workspace/webpack-babel-multi-target-plugin/node_modules/webpack/lib/Compilation.js:1137:9)
        at hooks.make.callAsync.err (/home/ranger/workspace/webpack-babel-multi-target-plugin/node_modules/webpack/lib/Compiler.js:545:17)
        at _done (eval at create (/home/ranger/workspace/webpack-babel-multi-target-plugin/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:9:1)
        at _promise1.then._result1 (eval at create (/home/ranger/workspace/webpack-babel-multi-target-plugin/node_modules/tapable/lib/HookCodeFactory.js:32:10), <anonymous>:31:22)
        at <anonymous>
        at process._tickDomainCallback (internal/process/next_tick.js:229:7)
     @ ./src/components/HelloWorld.vue?vue&type=script&lang=js&babel-target=modern
     @ ./src/components/HelloWorld.vue
     @ /home/ranger/workspace/webpack-babel-multi-target-plugin/node_modules/babel-loader/lib??ref--3!./node_modules/vue-loader/lib!./src/App.vue?vue&type=script&lang=js&babel-target=modern
     @ ./src/App.vue?vue&type=script&lang=js&babel-target=modern
     @ ./src/App.vue?babel-target=modern
     @ ./src/main.js?babel-target=modern

[DanielSchaffer]

Looks like something weird is up with your branch here... I'm going to close and just make the change to the example project on my end.