Memory error 'end corrupt' reports for deform groups... can't find it yet,

but this code ensures the strcpy() is using BLI_strncpy now, and it uses
more clear names for the mallocs.

source/blender/src/meshtools.c

@@ -205,7 +205,7 @@ void join_mesh(void)
 						}
 					}
 					if (!odg){
-						odg = MEM_callocN (sizeof(bDeformGroup), "deformGroup");
+						odg = MEM_callocN (sizeof(bDeformGroup), "join deformGroup");
 						memcpy (odg, dg, sizeof(bDeformGroup));
 						BLI_addtail(&ob->defbase, odg);
 					}