Make sure that with -overwrite the axial mesh is written back to constant

git-svn-id: svn://svn.code.sf.net/p/openfoam-extend/svn/trunk/Breeder_1.6/utilities/mesh/manipulation/MakeAxialMesh@2053 e4e07f05-0c2f-0410-a05a-b8ba57e0c909