title: Logstash: convert lambert to latitude and longitude
body: <p>I am working on a project where I have in my input data some coordinates in lambert. i would like to convert these coordinates in latitude and longitude. I found on internet a function in ruby to do it: <a href="https://github.com/yageek/lambert-ruby" rel="nofollow">https://github.com/yageek/lambert-ruby</a> . However, I don't think I can use it in logstash. Then, do you know if there is a function or a plugin in logstash.</p>
  
  <p>Thank you for your attention and your help.</p>
  
  <p>Joe</p>