add unity doc.

unity/PICO-Unity-Integration-SDK-release_3.4.0/package.json

@@ -0,0 +1,22 @@
+{
+  "name": "com.unity.xr.picoxr",
+  "displayName": "PICO Integration",
+  "version": "3.4.0",
+  "unity": "2021.3",
+  "description": "Provides display and input support for PICO devices.",
+  "keywords": [
+    "picoxr",
+    "xr",
+    "vr",
+    "virtual",
+    "xreditorsubsystem"
+  ],
+  "dependencies": {
+    "com.unity.xr.management": "4.0.0",
+    "com.unity.xr.interaction.toolkit": "2.0.0",
+    "com.unity.xr.core-utils": "2.3.0"
+  },
+  "unityRelease": "26f1",
+  "documentationUrl": "https://developer.picoxr.com/document/unity/",
+  "changelogUrl": "https://developer.picoxr.com/document/updates-unity/"
+}