function filter(obj, prop) {
  var omitKeys = ['debug', '_contents', 'fn'];
  if (typeof prop !== 'string' || prop === '') {
    return _.omit(_.cloneDeep(obj), omitKeys);
  }
  return _.omit(_.cloneDeep(get(obj, prop)), omitKeys);
}
Convenience method for debugging.

**Examples**

```js
{%= log(debug("app")) %}
{%= log(debug("app.cache.data")) %}

{%= log(debug("file")) %}
{%= log(debug("file.data")) %}

{%= log(debug()) %}
{%= log(debug("this")) %}
{%= log(debug("this.dest")) %}
```
@todo move to a helper