fix(htmlmin): disable the removeOptionalTags option.

Author: rebelliard

templates/common/root/_Gruntfile.js

@@ -384,8 +384,7 @@ module.exports = function (grunt) {
           collapseWhitespace: true,
           conservativeCollapse: true,
           collapseBooleanAttributes: true,
-          removeCommentsFromCDATA: true,
-          removeOptionalTags: true
+          removeCommentsFromCDATA: true
         },
         files: [{
           expand: true,