Initial add of GraphQL. Turns on GraphQL Content and GraphQL Voyager.

[tedbow]

Add GraphQL support and turn on.

Right now this just turns on GraphQL Content and GraphQL Voyager.

Remaining Tasks:

1. Determine if we should ship with configuration that presets "Exposed Content" as configured on "admin/config/graphql/content"
2. Determine which entity types to expose.
3. Actually test connecting to it.

Remaining questions:

1. Do we turn on all GraphQL modules?
2. If we turn on all GraphQL module GraphQL Voyager page become very complicated?
3. Change the existing toolbar item from "API" to "JSON API" and added new "Graph QL" item that points to the GraphQL Voyager page. is this ok or do we want 1 top level "API" still?
4. Is the "Authenication" page work for both API modules. If so should be move under "Access Control" toolbar item?