Vmigration-helper

Tweaking configuration to be compatible with newer versions of Django.

Fix up requirements so that library can be installed onto Python 3.7 running Django 1.11.17+
Update build scripts and README.md

* Cleaned up unused files
* README.md tweaks
* pyproject.toml tweaks

Standardize applied date/time display so that aware and naive datetimes are displayed consistently.

* If no records are in django_migrations (as is the case when a Django app is first created), return 0 for current ID
* wrap DB OperationException and just show terse error message instead of dumping stack trace