Allow connection plugin to accept a non-string cursor type

[jgnieuwhof]

Thanks for the connection plugin! I'm on a team that had made our own, one small change and we'll be able to deprecate ours, and use yours 😅.

The relay connection plugin currently hardcodes the cursor fields to be of the string type:

• Edge.cursor: https://github.com/graphql-nexus/schema/blob/develop/src/plugins/connectionPlugin.ts#L438
• PageInfo.startCursor: https://github.com/graphql-nexus/schema/blob/develop/src/plugins/connectionPlugin.ts#L478
• PageInfo.endCursor: https://github.com/graphql-nexus/schema/blob/develop/src/plugins/connectionPlugin.ts#L482

We'd like to be able to configure the cursor fields to be of a non-string, custom scalar type.

[tgriesser]

Ah interesting - I suppose this is allowed in the spec https://relay.dev/graphql/connections.htm#sec-Cursor

Should be easy to add... cursorType?

[jgnieuwhof]

That works, thank you!