function updateEntityProps (entityId, nextProps) {
    var entity = entities[entityId]
    entity.pendingProps = defaults({}, nextProps, entity.component.defaultProps || {})
    entity.dirty = true
    invalidate()
  }
Update an entity to match the latest rendered vode. We always
replace the props on the component when composing them. This
will trigger a re-render on all children below this point.

@param {Entity} entity
@param {String} path
@param {Object} vnode

@return {void}