fix(grunt): fixed unescaped references in clean:dist task

Author: DaftMonk

templates/common/Gruntfile.js

@@ -136,9 +136,9 @@ module.exports = function (grunt) {
           dot: true,
           src: [
             '.tmp',
-            '<%= yeoman.dist %>/*',
-            '!<%= yeoman.dist %>/.git*',
-            '!<%= yeoman.dist %>/Procfile'
+            '<%%= yeoman.dist %>/*',
+            '!<%%= yeoman.dist %>/.git*',
+            '!<%%= yeoman.dist %>/Procfile'
           ]
         }]
       },