def histogram(stat, value, opts=EMPTY_OPTIONS)
      send_stats stat, value, HISTOGRAM_TYPE, opts
    end
def histogram(stat, value, opts=EMPTY_OPTIONS)
      send_stats stat, value, HISTOGRAM_TYPE, opts
    end
Sends a value to be tracked as a histogram to the statsd server.

 @param [String] stat stat name.
 @param [Numeric] value histogram value.
 @param [Hash] opts the options to create the metric with
 @option opts [Numeric] :sample_rate sample rate, 1 for always
 @option opts [Array<String>] :tags An array of tags
 @example Report the current user count:
   $statsd.histogram('user.count', User.count)