better composer support

See version 2.0.0 for details about migrating to Kirby 3

Adapted for Kirby 3

The plugin was adapted to the new plugin architecture of Kirby 3.

Breaking Changes

The configuration options now have an official way of namespacing them, so they were changed:

• quote.default_style was changed to jbeyerstedt.quote.default_style

Composer Support

Composer support should work, but is untested. Please feel free to improve this (see #1).