Merge pull request #186 from Unity-Technologies/changelog_upgrade_notes_0.7.0

Changelog upgrade notes for 0.7.0

com.unity.perception/CHANGELOG.md

 
 ### Upgrade Notes
 
+#### Randomization Namespace Change
+The Randomization toolset has been moved out of the Experimental namespace. After upgrading to this version of the Perception package, please follow these steps:
+* Replace all references to `UnityEngine.Experimental.Perception.Randomization` with `UnityEngine.Perception.Randomization` in your C# code.
+* Open your Unity Scene file in a text editor and replace all mentions of `UnityEngine.Experimental.Perception.Randomization` with `UnityEngine.Perception.Randomization`, and save the file.
+
+#### Random Seed Generation
+Replace usages of `ScenarioBase.GenerateRandomSeed()` with `SamplerState.NextRandomState()` in your custom Randomizer code.
+
+#### Sampler Ranges 
+
+#### Tag Querying
+The `RandomizerTagManager.Query<T>` function now returns the tag object itself instead of the GameObject it is attached to. You will need to slightly modify your custom Randomizers to accommodate this change. Please refer to the included sample Randomizers as examples.
 
 ### Known Issues