Add `hall test` command

Yo Alex !

While I am working on a chapter of Guile Hacker Handbook, I started to write a small tutorial to create CLI app with Guile (on the model of Learning Rust by Writing a Command Line App in 15 Minutes).

I would like to rely the most upon Hall commands. In that in mind, running tests with a hall test (which could be a wrapper of something like autoreconf -vfi && ./configure && make check) could be cool !

Cheers