code: public List<Feature> getFeatures() {
  		return new EnumParameterList<Feature>(FEATURE) {
  			@Override
  			protected Feature _asObject(String value) {
  				return Feature.get(value);
  			}
  		};
  	}
docs: <p>
  Gets the FEATURE parameter values.
  </p>
  <p>
  This parameter is used by the {@link Conference} property. It defines the
  features that the conference supports (for example, audio and video).
  </p>
  <p>
  Changes to the returned list will update the {@link ICalParameters}
  object, and vice versa.
  </p>
  @return the features or empty list if none are set
  @see <a href=
  "https://tools.ietf.org/html/draft-ietf-calext-extensions-01#page-15" >
  draft-ietf-calext-extensions p.15</a>