Update clean script

lib/clean.js

@@ -12,7 +12,7 @@ exec('rm -rf ' + path.join(path.resolve('.'), 'content') + ' && mkdir content &&
       console.error('Error creating new project files.');
       return;
     }
-    exec ('cat ' + path.join('themes', 'cupper', 'data', 'README_BLANK.md') + ' > README.md', function(error, stdout, stderr) {
+    exec ('cat ' + path.join('themes', 'cupper', 'clean', 'README_BLANK.md') + ' > README.md', function(error, stdout, stderr) {
       if (error !== null) {
         console.error('Error initializing README file.');
         return;