update: no vue-2 compatability (doesn't work with current build)

* README.md

rollup.config.js

@@ -82,7 +82,7 @@ function createConfig(format, output, plugins = []) {
   output.sourcemap = !!process.env.SOURCE_MAP;
   output.banner = banner;
   output.externalLiveBindings = false;
-  output.globals = { 'vue-demi': 'VueDemi' };
+  output.globals = { 'vue': 'Vue' };
 
   const isProductionBuild = /\.prod\.js$/.test(output.file);
   const isGlobalBuild = format.startsWith('global');
@@ -111,7 +111,7 @@ function createConfig(format, output, plugins = []) {
   // during a single build.
   hasTSChecked = true;
 
-  const external = ['vue-demi'];
+  const external = ['vue'];
 
   const nodePlugins = [resolve(), commonjs({ include: 'node_modules/**' })];