Some alternate contrast colors for the dark theme grid

alternateContrast.patch

diff --git editor/js/Sidebar.Renderer.js editor/js/Sidebar.Renderer.js
index f48dd9a..e56d632 100644
--- editor/js/Sidebar.Renderer.js
+++ editor/js/Sidebar.Renderer.js
@@ -43,13 +43,16 @@ Sidebar.Renderer = function ( editor ) {
     var themeRow = new UI.Panel();
 	var originalColor;
 
-	var theme = new UI.Select().setOptions( [ 'Light', 'Dark' ] ).setWidth( '150px ').setColor( '#444' ).setFontSize( '12px ');
+	var theme = new UI.Select().setOptions( [ 'Light', 'Dark', 'DarkA', 'DarkB', 'DarkC' ] ).setWidth( '150px ').setColor( '#444' ).setFontSize( '12px ');
 	theme.onChange( function () {
 
 		switch ( this.value ) {
 
 			case '0': themeLink.href = 'css/light.css'; break;
 			case '1': themeLink.href = 'css/dark.css'; break;
+			case '2': themeLink.href = 'css/dark.css'; break;
+			case '3': themeLink.href = 'css/dark.css'; break;
+			case '4': themeLink.href = 'css/dark.css'; break;
 
 		}
 
diff --git editor/js/Viewport.js editor/js/Viewport.js
index e748e49..1ca5a39 100644
--- editor/js/Viewport.js
+++ editor/js/Viewport.js
@@ -412,8 +412,10 @@ var Viewport = function ( editor ) {
 		switch ( theme.selectedIndex ) {
 
 			case '0': grid.setColors( new THREE.Color( 0x444444 ), new THREE.Color( 0x888888 ) ); break;
-			case '1': grid.setColors( new THREE.Color( 0xbbbbbb ), new THREE.Color( 0x888888 )); break;
-
+			case '1': grid.setColors( new THREE.Color( 0x444444 ), new THREE.Color( 0x888888 ) ); break;
+			case '2': grid.setColors( new THREE.Color( 0xbbbbbb ), new THREE.Color( 0x888888 )); break;
+			case '3': grid.setColors( new THREE.Color( 0x1b1b1b ), new THREE.Color( 0x292929 ) ); break;
+			case '4': grid.setColors( new THREE.Color( 0x1d1d1d ), new THREE.Color( 0x444444 ) ); break;
 		}
 
 		// Force refresh