Update README.md

Fixed wrong README formatting.

README.md

 
 ## For Unity 2017.1 beta users
 SRP depends on PostProcessing submodule. Perform the following instructions to get a working copy of SRP:
-git clone https://github.com/Unity-Technologies/ScriptableRenderLoop
-git checkout unity-2017.1b5 (or the latest tag)
-git submodule update --init --recursive
+* git clone https://github.com/Unity-Technologies/ScriptableRenderLoop
+* git checkout unity-2017.1b5 (or the latest tag)
+* git submodule update --init --recursive
 
 ## For Unity 5.6 beta users