Generate config.h Message.hh needs the PACKAGE and VERSIONS macros, which won't be available after the build. So we use AC_CONFIG_HEADERS to generate a config.h to ship with the development package that contains these macros.
Prefix all binaries with topcom-. Several of the binaries (esp. cross and cube) have very generic names which may clash with other packages on the user's system. Other distros have taken a similar approach (e.g., Gentoo renames cube to topcom_cube and Fedora prefixes cross, cube, cyclic, hypersimplex, and lattice with TOPCOM-). We take the same approach as the nauty package -- prefix *everything*. This has the advantage of consistency, which is useful for other programs which may call TOPCOM, e.g., Macaulay2's Topcom package.
