chore(package): update gulp-typescript to version 3.1.5 (#403)
chore(package): update gulp-typescript to version 3.1.5 (#403)

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