Return list of features declared for module `yam`.

def get_features(self, yam):
        """Return list of features declared for module `yam`."""
        mcap = [ c for c in self.capabilities
                 if c.parameters.get("module", None) == yam ][0]
        if not mcap.parameters.get("features"): return []
        return mcap.parameters["features"].split(",")