Add missing Color.js.

src/color/Color.js

@@ -0,0 +1,42 @@
+Color = Base.extend({
+	beans: true,
+
+	/**
+	 * A value between 0 and 1 that specifies the color's alpha value.
+	 * All colors of the different subclasses support alpha values.
+	 */
+	getAlpha: function() {
+		return this._alpha;
+	},
+	
+	setAlpha: function(alpha) {
+		if (this._alpha == null || alpha == -1) this._alpha = -1;
+		else if (this._alpha < 0) this._alpha = 0;
+		else if (alpha > 1) this._alpha = 1;
+		else this._alpha = alpha;
+	},
+	
+	/**
+	 * Checks if the color has an alpha value.
+	 * 
+	 * @return {@true if the color has an alpha value}
+	 */
+	hasAlpha: function() {
+		return this._alpha != -1;
+	},
+	
+	statics: {
+		read: function(args, index) {
+			var index = index || 0, length = args.length - index;
+			if (length == 1 && args[index] instanceof Color) {
+				return args[index];
+			} else if (length != 0) {
+				var rgbColor = new RGBColor();
+				rgbColor.initialize.apply(rgbColor, index > 0
+						? Array.prototype.slice.call(args, index) : args);
+				return rgbColor;
+			}
+			return null;
+		}
+	}
+});