src/discriminator.js
function(model, schema) {
  for (var i in schema.statics) {
    model[i] = schema.statics[i];
  }
}
function(model, schema) {
  for (var i in schema.statics) {
    model[i] = schema.statics[i];
  }
}
/*
Register statics for this model
@param {Model} model
@param {Schema} schema