flatiron/winston — pull request #444 by pfcgarcia (2014-09-07 09:45:08+00:00)
Title: Exclude functions from cloned meta objects

When we add some custom function to Object.prototype, winston logs that code as well since clone function copies everything from meta object. E.g. cloned {} meta will have Object.prototype functions which is quite useless in meta I believe.

Resolves #420

Issue:

Defining new Object function:
```javascript
Object.prototype.hasOwnValue = function(val) {
for(var prop in this)
{
if(this.hasOwnProperty(prop) && this[prop] === val)
{
return true;
}
}

return false;
};
```

Writing some text to log without meta:
```javascript
logger.log("warn", "Logger initialized");`
```

And the result:
![image](https://cloud.githubusercontent.com/assets/3230176/4178043/17d39bf8-3673-11e4-9850-e298957264b5.png)