Django Let's Encrypt - 4.0.0

A quick introduction to this release:

• No major code changes have been made.
• This is to sync with the latest versions of python and Django available.
• If you are a happy user on the previous version v3.0.1, the upgrade should be painless **as long as you meet the new version minimums for both python and Django.
• I made the choice to make this a clean "major version" upgrade as the latest Django release schedules have really streamlined working with Django. So in order to not disrupt installations since this is a large minimum version change, the choice was made to make this the 4.0 release.

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This is a production-ready release of django-letsencrypt.
Please refer to the README of the project to get started.

• PyPI - django-letsencrypt

v4.0.0

• Breaking Changes
  • This was made as an overall major version bump due to the drastic supported
    version changes. However, the project and code mostly remain the same. This
    version sync allows the project to be easily kept up to date and upgraded.
  • As per the Django Project Docs.
    This project does a major version upgrade to only support:
    • Release Series 3.1 starting with version 3.1.2.
    • Release Series 3.0 starting with version 3.0.10.
    • Release Series 2.2 LTS starting with version 2.2.16.
  • This project supports the following python versions:
    • Python 3.6
    • Python 3.7
    • Python 3.8
  • pytz>=2020.1 is now required.
  • Travis Updates:
    • For the time being, we will continue to use travis.
    • Updated to support target versions as detailed for both Django and Python.
  • Operational Excellence Changes:
    • Updated .python-version file to latest values.
    • Dropping slack notification (for now).
    • Updated the example_project requirements.txt versions.
  • General Updates:
    • General README updates.
    • Updated copyright headers.