becasue adding rst directive is nothing to do with signals, maybe it will not work by passing settings to the signal. I trace the code and think that we could do something like [PYGMENTS_RST_OPTIONS](https://github.com/getpelican/pelican/blob/master/pelican/settings.py#L117) [does in the code](https://github.com/getpelican/pelican/blob/master/pelican/settings.py#L142).

We can move PYGMENTS_RST_OPTIONS to DEFAULT_CONFIG, and then add PELICAN_SETTINGS as global variable, copy the settings to PELICAN_SETTINGS in [read_settings](https://github.com/getpelican/pelican/blob/master/pelican/settings.py#L120). so in the plugin we can use something like:
```python
from pelican.settings import PELICAN_SETTINGS
```
to access the settings.
Please advise.