chore: add jimp dependency, icon padding script, and update configuration

node_modules/isomorphic-fetch/fetch-npm-browserify.js

@@ -0,0 +1,6 @@
+// the whatwg-fetch polyfill installs the fetch() function
+// on the global object (window or self)
+//
+// Return that as the export for use in Webpack, Browserify etc.
+require('whatwg-fetch');
+module.exports = self.fetch.bind(self);