fix(CoreModule): provide ViewTitleService for root only
fix(CoreModule): provide ViewTitleService for root only

rolandjitsu/angular-lab,rolandjitsu/ng2-lab,rolandjitsu/ng2-play,rolandjitsu/angular-lab,rolandjitsu/angular-lab,rolandjitsu/angular-lab,rolandjitsu/ng2-play,rolandjitsu/ng2-lab,rolandjitsu/ng2-play,rolandjitsu/ng2-lab,rolandjitsu/ng2-lab,rolandjitsu/ng2-play