Get Automake to recognise ggspec's TAP output

I've converted the Automake-TAP example into an Automake-TAP-ggspec example. On running a `make check` now, Automake now understand's ggspec's TAP test output and lists individual test descriptions along with their assertion result.

I'm still hazy about a few things:

- How to suppress Guile's automatic compilation messages from showing up in the `test-suite.log`, as you have in aiscm

- How to get Automake to run the Scheme test scripts as actual Guile files, so that I can remove the shebang lines from the tops of the files

- And probably on a related note, how exactly the `SCM_LOG_COMPILE` variable works in `Makefile.am` and how I can pass into it Guile command line switches.

This is working for me against current ggspec master. Hope it works on your end :-)