Added _getSurveyRecordFor method to Survey View.
Added _getSurveyRecordFor method to Survey View.

This method is used by the Take view to get the right SurveyRecord for the current request. Subclassed Views that want to fetch their records in another way can override this method.

rhyolight/nupic.son,rhyolight/nupic.son,rhyolight/nupic.son