If you like using online tools to hunt and gather your food, take note: Seamless and GrubHub, two of the better-known players in the mobile food-delivery business, announced today that they will be merging their services. GrubHub, which is privately owned, features the most restaurants of the two services, claiming 20,000 eateries in their online ordering network, compared to Seamless' 12,000. Seamless users, then, are going to get the better end of the deal right away, with the inclusion of GrubHub's additional dining options. GrubHub users should benefit from Seamless overall service, which…