fix(SDK): ensure custom Daydream code only executes when SDK selected

The Daydream SDK used code that was specific to the Google Daydream SDK
but did now have scripting defines surrounding it meaning it would
create an error unless the Google Daydream SDK was installed.

This has been resolved. Plus, the unwanted commented out code has been
removed and the xml documentation has been added to the Daydream SDK.

The documentation has also been auto generated for the Daydream SDK.

Author: thestonefox

Assets/VRTK/SDK/Daydream/DaydreamControllerLog.cs

@@ -1,18 +1,17 @@
-namespace VRTK
+#if VRTK_SDK_DAYDREAM
+namespace VRTK
 {
     using UnityEngine;
-    using System.Collections;
 
     /// <summary>
     /// DaydreamReach component uses touchpad to extend controller position out in front of user
     /// along the current controller orientation plane
     /// </summary>
     public class DaydreamReach : MonoBehaviour
     {
-        // controller to track, defaults to ./Controller but probably want a Pointer Joint like GvrControllerPointer/Laser
+        [Tooltip("Controller to track, defaults to ./Controller but probably want a Pointer Joint like GvrControllerPointer/Laser")]
         public Transform controller;
-
-        // maximum reach distance from controller origin
+        [Tooltip("Maximum reach distance from controller origin.")]
         public float reachDistance = 0.5f;
 
         private Vector3 positionOrigin;
@@ -79,10 +78,10 @@ private Vector2 GetTouch(int origin = 5)
                     touch.y = touch.y * 2f - 1f;
                     touch.x = touch.x * 2f - 1f;
                     break;
-                    // todo...
             }
 
             return touch;
         }
     }
-}
+}
+#endif

Assets/VRTK/SDK/Daydream/DaydreamControllerLog.cs.meta

@@ -5,7 +5,7 @@ namespace VRTK
     using UnityEngine;
 
     /// <summary>
-    /// The Sim Boundaries SDK script provides dummy functions for the play area bounderies.
+    /// The Daydream Boundaries SDK script provides dummy functions for the play area bounderies.
     /// </summary>
     public class SDK_DaydreamBoundaries : SDK_BaseBoundaries
     {