add refs #xxx to commit message

prepare-commit-msg

#!/usr/bin/env ruby

message_file = ARGV[0]
message = File.read(message_file)

branch = `git branch`.scan(/\* (.*)/).flatten[0]
exit 0 if branch == "master"

issue_no = branch.scan(/(\d{3,})/).flatten[0]
exit 0 if issue_no.nil?

message = "#refs ##{issue_no} \n" + message unless message.match("refs #")

File.open(message_file, "w") do |file|
  file.write message 
end