object validation

It's an object validation and sanitization for checkBody.
```
request.body: {
    prop: 'name',
    object: {
        property: 'property test',
        child: {
            property: 'child property test',
            child: {
                property: 'child property test'
            }
        }
    }
}
```
```
this.checkBody('name').notEmpty().len(3,20);
this.checkBody('object.property').notEmpty().len(3,20);
this.checkBody('object.child.property').notEmpty().len(3,20);
```

Also, `this.body = this.errors;` at line 198 was causing an error when running tests.
The next line returns `this.body = 'ok';`, so I commented the first one.