Added numberOfRows and numberOfColumns to CPCollectionView.

Reviewed by me.

AppKit/CPCollectionView.j

@@ -436,6 +436,23 @@
     return _maxNumberOfColumns;
 }
 
+/*!
+    Returns the current number of rows
+*/
+- (unsigned)numberOfRows
+{
+    return _numberOfRows;
+}
+
+/*!
+    Returns the current number of columns
+*/
+
+- (unsigned)numberOfColumns
+{
+    return _numberOfColumns;
+}
+
 /*!
     Sets the minimum size for an item
     @param aSize the new minimum item size