title: How to change a ModelChoiceField using different QuerySet, after update of text input using jQuery?
body: <p>I have a django reporting form , basically like the one here:</p>
  
  <pre><code>class EntryForm(ModelForm):
      year = forms.IntegerField()
      month = forms.ModelChoiceField(queryset = ... )
      report_category = form.ModelChoiceField(queryset = ... ) # FKey to some category model
      report_text = forms.CharField()
  </code></pre>
  
  <p>Initially, user would type in the year value into the text input box, select month, then select category and type the report.</p>
  
  <p>now I want the month dropdown to be populated with the list of months that have no reports yet. After January 2014 report submitted, then next time the user type in the year 2014, the dropdown will be populated with only 11 months (minus January).</p>
  
  <p>I know how to get the querysets done, but I'm still confused as to how to make jQuery/AJAX part for the change on dropdown, after the text input lose focus.</p>