docs: add usage example

Author: Daniel Schmidt

README.md

@@ -0,0 +1,43 @@
+# Reactive GraphQL React
+
+React Hook bindings for [reactive-graphql](https://github.com/mesosphere/reactive-graphql).
+
+## Usage
+
+```ts
+import getReactiveGraphqlReact from "reactive-graphql-react";
+
+const schema = getSchema(); // get a GraphQL schema
+const queryGraphql = getReactiveGraphqlReact(schema); // get the hook
+
+export default function MyComponent() {
+  // Always up-to-date data
+  const [result, error] = queryGraphql(`
+        query {
+            posts {
+                title
+                author {
+                    name
+                }
+            }
+        }
+    `);
+  if (error) {
+    return <h3>There has been an error fetching the data</h3>;
+  }
+
+  if (!result) {
+    return <h3>Loading, please wait</h3>;
+  }
+
+  const {
+    data: { posts }
+  } = result;
+
+  return <PostList items={posts} />;
+}
+```
+
+## License
+
+MIT