fixed graphql docs, added graphql tutorial

docs/source/api/graphql.md

@@ -0,0 +1,15 @@
+---
+title: GraphQL API Reference
+permalink: /api/graphql/
+---
+
+We provide all services that Talk can provide via the GraphQL API documented
+below. For a primer about GraphQL, visit http://graphql.org/.
+
+If you're already familiar with GraphQL, visit
+[GraphQL API Overview](/talk/api/overview/) to see how to
+interact with Talk's GraphQL endpoint.
+
+# GraphQL Schema
+
+{% graphqldocs ../../client/coral-framework/graphql/introspection.json %}