def can_block?(friendable)
      active? && (approved? || (pending? && self.friend_id == friendable.id && friendable.class.to_s == Amistad.friend_model))
    end
def can_block?(friendable)
      active? && (approved? || (pending? && self.friend_id == friendable.id && friendable.class.to_s == Amistad.friend_model))
    end
returns true if a friendship can be blocked by given friendable