Some extra configuration options for YUIDOC integration

Configuration options added to integrate it easily with YUIDOC:

```javascript
// Whether there should be blank lines added between var sections
 "jsdocs_spacer_between_var_sections": false,

 // indicates whether the @property tag should be added automatically (var blocks)
 "jsdocs_autoadd_property_tag": false,

 // indicates whether the @default tag should be added automatically (var blocks)
 "jsdocs_autoadd_default_tag": false
```
- Spacer between var sections by configuration, it can be different from the functions spacer.
- Property tag autoadd option for vars added in the configuration file.
- Default tag autoadd option for vars added in the configuration file.