Update webpack-manifest-plugin
Update webpack-manifest-plugin

...to match https://github.com/danethurber/webpack-manifest-plugin
georgemarshall/DefinitelyTyped,markogresak/DefinitelyTyped,magny/DefinitelyTyped,magny/DefinitelyTyped,borisyankov/DefinitelyTyped,georgemarshall/DefinitelyTyped,georgemarshall/DefinitelyTyped,dsebastien/DefinitelyTyped,georgemarshall/DefinitelyTyped,mcliment/DefinitelyTyped,dsebastien/DefinitelyTyped,borisyankov/DefinitelyTyped