chore(package): update webpack-merge to version 0.19.0
chore(package): update webpack-merge to version 0.19.0

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mseemann/angular2-mdl-ext,kononenko-a-m/angular2-mdl-ext,mseemann/angular2-mdl-ext,kononenko-a-m/angular2-mdl-ext,mseemann/angular2-mdl-ext,kononenko-a-m/angular2-mdl-ext,kononenko-a-m/angular2-mdl-ext,mseemann/angular2-mdl-ext