title: Django admin list_display short_description
body: <p>In django admin, If we define an element for list_display we can assign <code>short_description</code> for that field as </p>
  
  <pre><code>class PersonAdmin(admin.ModelAdmin):
      list_display = ('upper_case_name','age')
  
      def upper_case_name(self, obj):
          return ("%s %s" % (obj.first_name, obj.last_name)).upper()
      upper_case_name.short_description = 'Name'
  </code></pre>
  
  <p>But what if I would like to change short description of age field ?
  I would like to show the header of <code>Age</code> field as <code>Person's Age</code> instead <code>Age</code>. Of course, I can write custom functions as <code>upper_case_name</code> for each field but it is a bad solution I think.</p>
  
  <p>Could you suggest me any easy way to do this ?
  Thanks</p>