Jaque Silva | Nurphoto | Getty ImagesComcast plans to launch a new advertising platform that will make it easier for smaller businesses to buy ad time — and, the company hopes, to beckon some advertisers away from social media and digital outlets and over to traditional TV's streaming businesses.On Monday, Comcast announced the creation of Universal Ads, a new platform for advertisers to buy spots on premium video content on the streaming businesses of traditional media companies. The announceme...