fix(grunt:cdnify): preserve cdnified scripts in build

Previously, the script references in index.html that were changed by the cdnify step would later
be overwritten by the usemin task. Now, cdnify runs before useminPrepare and the usemin task is
configured to include references for cdnified scripts right before the actual block replacements.

Author: raphinesse

templates/common/root/_Gruntfile.js

@@ -363,7 +363,7 @@ module.exports = function (grunt) {
     // concat, minify and revision files. Creates configurations in memory so
     // additional tasks can operate on them
     useminPrepare: {
-      html: '<%%= yeoman.app %>/index.html',
+      html: '<%%= yeoman.dist %>/index.html',
       options: {
         dest: '<%%= yeoman.dist %>',
         flow: {
@@ -391,6 +391,17 @@ module.exports = function (grunt) {
         ],
         patterns: {
           js: [[/(images\/[^''""]*\.(png|jpg|jpeg|gif|webp|svg))/g, 'Replacing references to images']]
+        },
+        blockReplacements: {
+          // Include cdnified scripts followed by usemin dest script
+          js: function (block) {
+            var scripts = block.src.filter(function (src) {
+              return src.startsWith('//');
+            }).concat(block.dest);
+            return scripts.map(function (src) {
+              return '<script src="' + src + '"></script>';
+            }).join('\n');
+          }
         }
       }
     },
@@ -495,6 +506,14 @@ module.exports = function (grunt) {
 
     // Copies remaining files to places other tasks can use
     copy: {
+      html: {
+        files: [{
+          expand: true,
+          cwd: '<%= yeoman.app %>',
+          src: '*.html',
+          dest: '<%= yeoman.dist %>',
+        }],
+      },
       dist: {
         files: [{
           expand: true,
@@ -503,7 +522,6 @@ module.exports = function (grunt) {
           dest: '<%%= yeoman.dist %>',
           src: [
             '*.{ico,png,txt}',
-            '*.html',
             'images/{,*/}*.{webp}',
             'styles/fonts/{,*/}*.*'
           ]
@@ -606,14 +624,15 @@ module.exports = function (grunt) {
     'clean:dist',
     'wiredep',<% if (typescript) { %>
     'tsd:refresh',<% } %>
+    'copy:html',
+    'cdnify',
     'useminPrepare',
     'concurrent:dist',
     'postcss',
     'ngtemplates',
     'concat',
     'ngAnnotate',
     'copy:dist',
-    'cdnify',
     'cssmin',
     'uglify',
     'filerev',