breaks with webpack > 4

[basaran]

Hello, it appears gabiseabra/google-fonts-webpack-plugin breaks with webpack 4. Could you please update the README?

This seems to be the default root package for google-fonts-webpack-plugin so, there is probably quite a few people who try this first like me and go into a debugging cycle.

yarn run v1.22.4                                                                          
$ vue-cli-service serve                                                                    
INFO  Starting development server...
10% building 2/2 modules 0 active(node:29517) DeprecationWarning: Tapable.plugin is deprecated. Use new API on `.hooks` instead       

beyonk-adventures/google-fonts-webpack-plugin is compatible with webpack > 4.

webpack/webpack#6568

[Rycochet]

Duplicate of #24 from more than two years ago

[basaran]

My request was to include this in the README. So, when someone has an issue and visits the github page, they could be alarmed as to why. This is the package that gets installed by default when you to npm or yarn without the repo prefix. It will probably make somebody's life easier.