Add patch for wxWidgets 3 to fix scrolling on OSX.

=== modified file 'src/generic/scrlwing.cpp'

--- src/generic/scrlwing.cpp	2013-12-16 05:42:30 -0800

+++ src/generic/scrlwing.cpp	2014-10-21 01:19:02 -0700

@@ -214,9 +214,6 @@

         return true;

     }

-    if ( processed && event.IsCommandEvent())

-        return true;

-

     // For wxEVT_PAINT the user code can either handle this event as usual or

     // override virtual OnDraw(), so if the event hasn't been handled we need

     // to call this virtual function ourselves.

@@ -235,6 +232,11 @@

         return true;

     }

+    // If the user code handled this event, it should prevent the default 

+    // handling from taking place, so don't do anything else in this case. 

+    if ( processed ) 

+        return true; 

+

     if ( evType == wxEVT_CHILD_FOCUS )

     {

         m_scrollHelper->HandleOnChildFocus((wxChildFocusEvent &)event);

=== modified file 'src/generic/vscroll.cpp'

--- src/generic/vscroll.cpp	2013-12-16 05:42:30 -0800

+++ src/generic/vscroll.cpp	2014-10-21 01:19:09 -0700

@@ -89,9 +89,6 @@

         return true;

     }

-    if ( processed && event.IsCommandEvent())

-        return true;

-

     // For wxEVT_PAINT the user code can either handle this event as usual or

     // override virtual OnDraw(), so if the event hasn't been handled we need

     // to call this virtual function ourselves.

@@ -110,6 +107,11 @@

         return true;

     }

+    // If the user code handled this event, it should prevent the default 

+    // handling from taking place, so don't do anything else in this case. 

+    if ( processed ) 

+        return true; 

+

     // reset the skipped flag (which might have been set to true in

     // ProcessEvent() above) to be able to test it below

     bool wasSkipped = event.GetSkipped();