title: Select2 4.0.0 select before Ajax response
body: <p>I want the user, when using the input to be able to :</p>
  
  <p>1 : Fetch data from server when typing, then select according to proposition</p>
  
  <p>2 : Or If the user knows what he wants he should be able to type exactly what he wants before the data is fetched and then press enter</p>
  
  <p>The requirement 1: works perfectly. The fact is I really don't know how to handle the 2. Currently when the user is typing, he can,t press enter before the data is fetched. I looked at the doc trying to find some kind of options enabling this but it seems like there is not.</p>
  
  <p>If you ever had to implement that kind of behaviors I am curious about it. I have a few tweak in minds but I'd really like to use a native behavior.</p>