npm run build appears to be broken after fresh npm install on master

[davnicwil]

Fresh clone, on master.

Run npm i

Run npm run build

Get the following error for uglify - warnings not a supported option

src/index.js → dist/react-chartjs-2.min.js...
[!] (uglify plugin) Error: Error transforming bundle with 'uglify' plugin: `warnings` is not a supported option
Error: Error transforming bundle with 'uglify' plugin: `warnings` is not a supported option
    at error (/my--path/react-chartjs-2/node_modules/rollup/dist/rollup.js:181:12)
    at /my--path/react-chartjs-2/node_modules/rollup/dist/rollup.js:9494:5

[davnicwil]

Opened a PR that fixes this.

The warnings option moved in uglify from options.compress to the top level options object.