Remove django-pwa and provide meta/manifest through own views and templates

CHANGELOG.rst

aleksis/core/settings.py

aleksis/core/static/js/main.js

aleksis/core/templates/core/base.html

aleksis/core/templates/core/partials/meta.html

aleksis/core/urls.py

aleksis/core/util/core_helpers.py

aleksis/core/views.py

poetry.lock

pyproject.toml