Drop sites framework

See merge request !43

Update .gitignore

See merge request !41

Update .prettierignore

See merge request !42

Update tox.ini

See merge request !35

Update .dev-js/package.json

See merge request !36

Update pyproject.toml

See merge request !33

Update .gitignore

See merge request !37

Update tox.ini

See merge request !34

Resolve "Adapt to Core 4.0"

Closes #17

See merge request !31

Update tox.ini

See merge request !32

Update .eslintrc.js

See merge request !29

Update pyproject.toml

See merge request !30

Prepare release 2.0b0

See merge request !27