Modify build command so that mustache.js can be built on Windows

Windows shell does not recognize 'single quotes' the same way as bash. The 'single quotes' in the build command have been changed to "double quotes" instead.

package.json

@@ -28,7 +28,7 @@
     "url": "https://raw.github.com/janl/mustache.js/{version}/mustache.js"
   },
   "scripts": {
-    "build": "rollup mustache.mjs --file mustache.js --format umd --name Mustache --banner '// This file has been generated from mustache.mjs' && uglifyjs mustache.js > mustache.min.js",
+    "build": "rollup mustache.mjs --file mustache.js --format umd --name Mustache --banner \"// This file has been generated from mustache.mjs\" && uglifyjs mustache.js > mustache.min.js",
     "test": "npm run test-lint && npm run test-unit",
     "test-lint": "eslint mustache.mjs bin/mustache test/**/*.js",
     "test-unit": "mocha --reporter spec test/*-test.js",