validate (Irc::Bot::Config::Value)

    # File lib/rbot/config.rb, line 104
        def validate(val, validator  = @validate)
          case validator
          when false, nil
            return true
          when Proc
            return validator.call(val)
          when Regexp
            raise ArgumentError, "validation via Regexp only supported for strings!" unless String === val
            return validator.match(val)
          else
            raise ArgumentError, "validation type #{validator.class} not supported"
          end
        end