wip/cligen 7.1.0 NetBSD

CLIgen is a Command-Line Interface generator.

Well, actually it is not really a generator, since it does not generate code for CLI:s. Instead, it builds and interprets datastructures (a parse-tree) which a library (libcligen) interprets in runtime. It is fast and efficient and helps you develop CLI:s easier. You enter a CLI syntax in a text file, and write callback functions in C. The callback functions add the semantics, that is, what the commands in the CLI are supposed to do.