Support mapping graphql resolvers to specific endpoints.

[notadamking]

While GraphQL traditionally has a single entry point for all Queries and Mutations, REST usually organizes both across routes. For example, the following GraphQL Schema:

type Query {
   user(id: string): User
   userPermissions(userId: string): UserPermissions
}

type Mutation {
   updateUserPermissions(userId: string, permissions: UserPermissions): UserPermissions
}

would traditionally be implemented in REST in the following routes:

• `GET /users/:id``
• GET /users/:id/permissions
• POST /users/:id/permissions

but this sort of organization of REST routes seems to currently be impossible, leading to undesired rest routes such as :

• `GET /users``
• GET /userPermissions
• POST /userPermissions

which seems fine at first, but not as the API surface area grows and organization of routing becomes very important.