Added a new group Cocoa Compatability for the empty compatability

classes like CPMutableArray

Foundation/CPArray.j

@@ -1206,6 +1206,9 @@
 @end
 
 /*!
+    @class CPMutableArray
+    @ingroup compatability
+
     This class is just an empty subclass of CPArray.
     CPArray already implements mutable methods and
     this class only exists for source compatability.

Foundation/CPAttributedString.j

@@ -796,6 +796,9 @@
 @end
 
 /*!
+    @class CPMutableAttributedString
+    @ingroup compatability
+
     This class is just an empty subclass of CPAttributedString.
     CPAttributedString already implements mutable methods and
     this class only exists for source compatability.

Foundation/CPDictionary.j

@@ -597,6 +597,9 @@
 @end
 
 /*!
+    @class CPMutableDictionary
+    @ingroup compatability
+
     This class is just an empty subclass of CPDictionary.
     CPDictionary already implements mutable methods and
     this class only exists for source compatability.

Foundation/CPIndexSet.j

@@ -819,6 +819,9 @@ var CPIndexSetCountKey              = @"CPIndexSetCountKey",
 @end
 
 /*!
+    @class CPMutableIndexSet
+    @ingroup compatability
+
     This class is an empty of subclass of CPIndexSet.
     CPIndexSet already implements mutable methods, and
     this class only exists for source compatability.

Foundation/CPSet.j

@@ -484,6 +484,9 @@ var CPSetObjectsKey = @"CPSetObjectsKey";
 @end
 
 /*!
+    @class CPMutableSet
+    @ingroup compatability
+
     This class is just an empty subclass of CPSet.
     CPSet already implements mutable methods and
     this class only exists for source compatability.

Foundation/Foundation.j

@@ -70,4 +70,5 @@
 
     @defgroup appkit AppKit
     @defgroup foundation Foundation
+    @defgroup compatability Cocoa Compatability
 */