Cleanup sandcastle and docs for ground atmosphere

Apps/Sandcastle/gallery/Atmosphere.html → Apps/Sandcastle/gallery/Ground Atmosphere.html

@@ -4,7 +4,7 @@
     <meta charset="utf-8">
     <meta http-equiv="X-UA-Compatible" content="IE=edge">
     <meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, minimum-scale=1, user-scalable=no">
-    <meta name="description" content="Adjust hue, saturation, and brightness of the sky/atmosphere.">
+    <meta name="description" content="Adjust lighting on the globe as seen from space.">
     <meta name="cesium-sandcastle-labels" content="Showcases">
     <title>Cesium Demo</title>
     <script type="text/javascript" src="../Sandcastle-header.js"></script>
@@ -93,7 +93,6 @@
 var toolbar = document.getElementById('toolbar');
 Cesium.knockout.applyBindings(viewModel, toolbar);
 
-// Make the skyAtmosphere's HSB parameters subscribers of the viewModel.
 function subscribeParameter(name) {
     Cesium.knockout.getObservable(viewModel, name).subscribe(
         function(newValue) {

CHANGES.md

@@ -13,7 +13,6 @@ Change Log
 ### 1.50 - 2018-10-01
 
 ##### Breaking Changes :mega:
-* Renamed Ground Clamping Sandcastle example to [Clamp to Terrain](https://cesiumjs.org/Cesium/Apps/Sandcastle/index.html?src=Clamp%20to%20Terrain.html).
 * Clipping planes on tilesets now use the root tile's transform, or the root tile's bounding sphere if a transform is not defined. [#7034](https://github.com/AnalyticalGraphicsInc/cesium/pull/7034)
     * This is to make clipping planes' coordinates always relative to the object they're attached to. So if you were positioning the clipping planes as in the example below, this is no longer necessary:
     ```javascript

Source/Scene/Globe.js

@@ -136,7 +136,9 @@ define([
         this.enableLighting = false;
 
         /**
-         * Enable the ground atmosphere.
+         * Enable the ground atmosphere, which is drawn over the globe when viewed from a distance between <code>lightingFadeInDistance</code> and <code>lightingFadeOutDistance</code>.
+         *
+         * @demo {@link https://cesiumjs.org/Cesium/Apps/Sandcastle/index.html?src=Ground%20Atmosphere.html|Ground atmosphere demo in Sandcastle}
          *
          * @type {Boolean}
          * @default true
@@ -145,7 +147,7 @@ define([
 
         /**
          * The distance where everything becomes lit. This only takes effect
-         * when <code>enableLighting</code> is <code>true</code>.
+         * when <code>enableLighting</code> or <code>showGroundAtmosphere</code> is <code>true</code>.
          *
          * @type {Number}
          * @default 10000000.0
@@ -154,7 +156,7 @@ define([
 
         /**
          * The distance where lighting resumes. This only takes effect
-         * when <code>enableLighting</code> is <code>true</code>.
+         * when <code>enableLighting</code> or <code>showGroundAtmosphere</code> is <code>true</code>.
          *
          * @type {Number}
          * @default 20000000.0

Source/Scene/SkyAtmosphere.js

@@ -51,7 +51,7 @@ define([
      * {@link http://http.developer.nvidia.com/GPUGems2/gpugems2_chapter16.html|Accurate Atmospheric Scattering}
      * in GPU Gems 2.
      * <p>
-     * This is only supported in 3D.  atmosphere is faded out when morphing to 2D or Columbus view.
+     * This is only supported in 3D. Atmosphere is faded out when morphing to 2D or Columbus view.
      * </p>
      *
      * @alias SkyAtmosphere
@@ -62,6 +62,8 @@ define([
      * @example
      * scene.skyAtmosphere = new Cesium.SkyAtmosphere();
      *
+     * @demo {@link https://cesiumjs.org/Cesium/Apps/Sandcastle/index.html?src=Sky%20Atmosphere.html|Sky atmosphere demo in Sandcastle}
+     *
      * @see Scene.skyAtmosphere
      */
     function SkyAtmosphere(ellipsoid) {