add functional component warning

Author: yyx990803

Diff for: lib/compiler.js

@@ -126,6 +126,13 @@ compiler.compile = function (content, filePath, cb) {
     // template
     var template = resolvedParts.template
     if (template) {
+      if (process.env.NODE_ENV !== 'production') {
+        output +=
+          'if (__vue__options__.functional) {console.error("' +
+            '[vueify] functional components are not supported and ' +
+            'should be defined in plain js files using render functions.' +
+          '")}\n'
+      }
       output +=
         '__vue__options__.render = ' + template.render + '\n' +
         '__vue__options__.staticRenderFns = ' + template.staticRenderFns + '\n'

Diff for: package.json

@@ -32,7 +32,7 @@
     "source-map": "^0.5.6",
     "through": "^2.3.6",
     "vue-hot-reload-api": "^2.0.1",
-    "vue-template-compiler": "^2.0.0-alpha.3"
+    "vue-template-compiler": "^2.0.0-alpha.8"
   },
   "devDependencies": {
     "babel-core": "^6.0.0",