Fixed an incorrect error message in the Terrain component.
Fixed an incorrect error message in the Terrain component.

--HG--
branch : v1-7

jhu-lcsr-forks/ogre,nezticle/ogre,largerussiangames/ogre,nezticle/ogre,jhu-lcsr-forks/ogre,jhu-lcsr-forks/ogre,vancepym/ogre,jhu-lcsr-forks/ogre,nezticle/ogre,vancepym/ogre,largerussiangames/ogre,jhu-lcsr-forks/ogre,largerussiangames/ogre,largerussiangames/ogre,vancepym/ogre,vancepym/ogre,nezticle/ogre,vancepym/ogre