Updated readme structure/references

integrations/Unity3D/README.md

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+Unity3D + ZeroTier SDK
+====
+
+Welcome!
+
+We want your Unity apps to talk *directly* over a flat, secure, no-config virtual network without sending everything into the "cloud". Thus, we introduce the ZeroTier-Unity3D integration!  
+
+Our implementation currently intends to be the bare minimum required to get your Unity application to talk over ZeroTier virtual networks. As a result, we've created an API that is very similar to the built-in Unity LLAPI. It's possible that higher-level functionality could be added in the future. 
+
+***
+## Adding ZeroTier to your Unity app
+
+**Step 1: Create virtual ZeroTier [virtual network](https://my.zerotier.com/)**
+
+**Step 2: Add plugin**
+ - Create a folder called `Plugins` in `Assets`
+ - Place `ZeroTierUnity.bundle` in that folder
+
+**Step 3: Add script to some `GameObject`**
+ - Drag our `ZeroTier.cs` native plugin wrapper onto any `GameObject`
+
+
+***
+## Examples
+
+Calling `ZeroTier.Init()` will start the network service in a separate thread. You can check if the service is running by checking `ZeroTier.IsRunning()`. Then, connecting and sending data to another endpoint would look something like the following:
+
+```
+public void zt_sample_network_test_thread()
+{
+	// Prepare sample data buffer
+	byte[] buffer = new byte[1024];
+	Stream stream = new MemoryStream(buffer);
+	BinaryFormatter f = new BinaryFormatter();
+	f.Serialize ( stream , "Welcome to the machine! (from Unity3D)" );
+
+	// Connect and send
+	int error;
+	Connect (0, "192.168.0.6", 8887, out error);
+	Send(connfd,buffer,0, out error);
+}
+```
+
+Finally, when you're done running the service you can call `ZeroTier.Terminate()`
+
+***
+## API  
+
+The API is designed to resemble the Unity LLAPI, so you'll see a few familiar functions but with a slight twist. 
+
+- `Join(nwid)`: Joins a ZeroTier virtual network
+- `Leave(nwid)`: Leaves a ZeroTier virtual network
+- `AddHost(port)`: Creates a socket, and binds to that socket on the address and port given
+- `Connect(fd, ip_address, port, out error)`: Connects to an endpoint associated with the given `fd` 
+- `Send(fd, buf, pos, out error)`: Sends data to the endpoint associated with the given `fd`
+- `Recv(fd, buf, out error)`: Receives data from an endpoint associated with the given `fd`
+- `Disconnect(fd)`: Closes a connection with an endpoint
+
+***
+## Design and structure of the ZeroTier Unity OSX Bundle
+
+XCode:
+New XCode project
+Select Cocoa bundle as target
+Add C linkages to external functions
+Build as 64bit (not universal)
+
+Unity:
+Select x86_64 build target in `Build Settings`
+In new C# script asset:
+
+```
+[DllImport ("ZeroTierUnity")]
+private static extern int unity_start_service ();
+```
+
+Add asset to GameObject
+Start ZT service
+
+***
+## Future Roadmap  
+With the ZeroTier sockets API in place, higher-level functionality such as lobbies, chat, and object synchronization could easily be built on top.
+
+