Proper SolverHandler serialization

Author: keveleigh

Assets/MixedRealityToolkit-Examples/Demos/Solvers/Prefabs/ChaseSource.prefab

@@ -120,6 +120,7 @@ MonoBehaviour:
   maintainScale: 1
   smoothing: 1
   lifetime: 0
+  SolverHandler: {fileID: 114229151188300204}
   referenceDirection: 1
   minDistance: 1
   maxDistance: 2

Assets/MixedRealityToolkit-Examples/Demos/Solvers/Prefabs/ChaseSourceWithOffset.prefab

@@ -176,6 +176,7 @@ MonoBehaviour:
   maintainScale: 1
   smoothing: 1
   lifetime: 0
+  SolverHandler: {fileID: 114911825043747796}
   referenceDirection: 1
   minDistance: 1
   maxDistance: 2

Assets/MixedRealityToolkit-Examples/Demos/Solvers/Prefabs/InBetweenSources.prefab

@@ -120,6 +120,7 @@ MonoBehaviour:
   maintainScale: 1
   smoothing: 1
   lifetime: 0
+  SolverHandler: {fileID: 114709813557731528}
   partwayOffset: 0.5
   trackedObjectForSecondTransform: 1
   secondTransformOverride: {fileID: 0}