title: Sublime Autocomplete that calls plugin
body: <p>I've create an autocomplete file that looks like that:</p>
  
  <pre><code>{
      "scope": "",
  
      "completions":
      [
              { "trigger": "ticket", "contents": "# ticket No.\"$1\" Status: $0" }
  
      ]      
  </code></pre>
  
  <p>}</p>
  
  <p>I'm working on a plugin that receives ticket number and returns status. Is it possible to enter the variable $1 when autocompleted and make the $0 variable filled by plugin function?</p>