ENH: use globalIndex gather in patch merging

...eshes/primitiveMesh/PatchTools/PatchToolsGatherAndMerge.C

src/sampling/sampledSet/sampledSet/sampledSet.C

src/sampling/sampledSet/sampledSets/sampledSets.C

src/sampling/sampledSet/sampledSets/sampledSetsTemplates.C

...sampledSurface/sampledSurfaces/sampledSurfacesTemplates.C

src/surfMesh/mergedSurf/mergedSurf.C