Editorial corrections to the documentation.

Added section to group similar functions in the documentation of wxGraphicsContext.
Fixed references to the section describing wxPGProperty attributes.

interface/wx/graphics.h

@@ -392,6 +392,12 @@ public:
 class wxGraphicsContext : public wxGraphicsObject
 {
 public:
+    /**
+        @name Creating a context
+
+        @{
+    */
+
     /**
         Creates a wxGraphicsContext from a wxWindow.
 
@@ -466,6 +472,9 @@ public:
     */
     static wxGraphicsContext* Create();
 
+    /** @}
+    */
+
     /**
         @name Clipping region functions