chore(package): update css-loader to version 0.26.4
chore(package): update css-loader to version 0.26.4

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mseemann/angular2-mdl,c1rno/angelhack_frontend_prototype,mseemann/angular2-mdl,c1rno/angelhack_frontend_prototype,mseemann/angular2-mdl,c1rno/angelhack_frontend_prototype,c1rno/angelhack_frontend_prototype,mseemann/angular2-mdl