rockspecs: remove debug line.

* build-aux/mkrockspecs.lua: Remove left-over debug line.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
yaml: spun off into a separate project.

Rather than ship and build our own yaml binding, spin it off to
http://github.com/gvvaughan/lyaml and depend on a new luarock
built from that.
* yaml/yaml.mk: Remove.
* Makefile.am: Adjust.
* specl/specl.mk (SPECL_CPATH): Remove.
(specl_install_edit, specl_inplace_edit): Adjust.
(specl_specl_DEPS): Remove yaml/lyaml.la.
* yaml/lua52compat.h, yaml/lyaml.c: Remove.
* configure.ac (LT_INIT): Remove, along with supporting configury.
(AC_CONFIG_HEADERS): Remove.
* specl-rockspec.lua (external_dependencies.YAML): Remove.
(dependencies): Add lyaml.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>