conflict with _OgreOctreeZonePluginExport def. in two files?

Hi,

decided to post some small warning-crushing report ... together with 8398 commit and GCC visibility support in CMake build system, OctreeZone plugin started to issue warnings about redefinition... there is _OgreOctreeZonePluginExport defined in both OgreTerrainZonePrerequisites.h and OgreOctreeZonePrerequisites.h, what more definitions differ slightly (with this from OgreTerrainZonePrerequisites.h supporting GCC Visibility and second not...) I guess this should be put to only one of those files? For example definition from OgreTerrainZonePrerequisites.h should be put to OgreOctreeZonePrerequisites.h? That's at least one of solutions I guess

cheers,
Andrzej.

== edit - I submitted patch, not masterpiece but works... probably 1000 different ways to make it nicer ... ticket id is 2694668

Thanks, I've applied a slightly modified version (used only OGRE_OCTREEZONEPLUGIN_EXPORTS and got rid of OGRE_TERRAINZONEPLUGIN_EXPORTS entirely, from CMake too).