Django 2.1+ support

[JacoBezuidenhout]

• django mail admin version:
• Django version: 2.2b1
• Python version: 3.6
• Operating System: MacOS

Description

I tried to add new outgoing email

What I Did

I got the error:

render() got an unexpected keyword argument 'renderer'

** From Django 2.1: Support for Widget.render() methods without the renderer argument is removed.
https://docs.djangoproject.com/en/2.1/releases/2.1/#features-removed-in-2-1

[delneg]

Check 0.2.0