Add install and usage docs

build.sbt

@@ -81,3 +81,4 @@ lazy val docs =
         )
       }
     )
+    .dependsOn(`flipt-sdk-server`.jvm)

docs/index.md

@@ -8,3 +8,44 @@
 - Implementation of a Scala Flipt OpenFeature provider
 - Implementation of a Scala LaunchDarkly OpenFeature provider, e.g. with
   [Catalyst](https://typelevel.org/catapult)
+
+## Installing
+
+```scala
+libraryDependencies += "io.cardell" % "ff4s-flipt-server-sdk" % "@VERSION@"
+```
+
+## Usage
+
+```scala mdoc
+import cats.effect.IO
+import org.http4s.ember.client.EmberClientBuilder
+import org.http4s.Uri
+import io.cardell.ff4s.flipt.FliptApi
+import io.cardell.ff4s.flipt.EvaluationRequest
+import io.cardell.ff4s.flipt.auth.AuthenticationStrategy
+
+val url: Uri = Uri.unsafeFromString("https://flipt.example.com")
+val token: String = "token"
+
+val resource = EmberClientBuilder
+    .default[IO]
+    .build
+    .map(client =>
+        FliptApi[IO](client, url, AuthenticationStrategy.ClientToken("token"))
+    )
+
+resource.use { flipt => 
+    for {
+        res <- flipt.evaluateBoolean(
+            EvaluationRequest(
+                namespaceKey = "default",
+                flagKey = "my-flag-1",
+                entityId = None,
+                context = Map.empty,
+                reference = None
+            )
+        )
+    } yield res.enabled
+}
+```

flake.nix

@@ -18,7 +18,7 @@
           imports = [ typelevel-nix.typelevelShell ];
           name = "ff4s-shell";
           typelevelShell = {
-            jdk.package = pkgs.jdk8;
+            jdk.package = pkgs.jdk11;
             nodejs.enable = true;
           };
         };