Cleanup manifest, random files, update install

Assets/ML-Agents/Timers.meta

@@ -1,8 +0,0 @@
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-guid: 416d62094ee56475abce2d0f5bb1dfbd
-folderAsset: yes
-DefaultImporter:
-  externalObjects: {}
-  userData: 
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Packages/manifest.json

@@ -10,7 +10,6 @@
     "com.unity.ide.vscode": "1.2.3",
     "com.unity.inputsystem": "1.1.0-pre.5",
     "com.unity.ml-agents": "2.1.0-exp.1",
-    "com.unity.ml-agents.extensions": "0.5.0-preview",
     "com.unity.multiplayer-hlapi": "1.0.6",
     "com.unity.postprocessing": "3.0.1",
     "com.unity.purchasing": "2.2.2",

README.md

@@ -14,7 +14,7 @@ To open this repository, you will need to install the [Unity editor version 2020
 
 Clone the `dodgeball-env` branch of this repository by running:
 ```
-git clone --single-branch --branch dodgeball-env https://github.com/Unity-Technologies/ml-agents.git
+git clone --single-branch --branch dodgeball-env https://github.com/Unity-Technologies/ml-agents.git ml-agents-dodgeball-env
 ```
 
 Open the root folder in Unity. Then, navigate to `Assets/Dodgeball/Scenes/TitleScreen.unity`, open it, and hit the play button to play against pretrained agents. You can also build this scene (along with the `Elimination.unity` and `CaptureTheFlag.unity` scenes into a game build and play from there.