Override default chunk manifest plugin

To use plugins like webpack-manifest-plugin the default plugin used to extract the webpack chunk manifest can be overriden.

Added in this version are the following configs params:

const inlineChunkManifestConfig = {
  /* all previous options still exist */
  manifestPlugins: [/* override default chunk manifest plugin(s) */],
  extractManifest: false // true is default. When set to false, manifestPlugins (incl default) are not applied
};