specl: fix --version and --help formatting with stdlib-33 getopt.

* src/specl.in (prog.version): Separate out copyright notice...
(prog.copyright): ...to here.
(prog.description): Latest stdlib getopt doesn't need double
newline paragraph separators.
* src/version.lua.in (M.COPYRIGHT_NOTICE): Rejustify slightly.
Point to gnu licenses webpage rather than COPYING file, which
might have been lost during installation!

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
specl: read yaml format spec files.

* yaml/lua52compat.h, yaml/yaml.c: New files.  Sources for yaml
module.
* yaml/yaml.mk: New file. Build yaml module.
* Makefile.am: Include it.
(lib_LTLIBRARIES): Initialise.
* configure.ac (AC_INIT): Bump version to 2.
(AM_INIT_AUTOMAKE): Use subdir-objects.
(LT_PREREQ, LT_INIT): Add libtool setup.
(AC_PROG_CC, AC_HEADER_STDC): Add C compiler setup.
(AC_CONFIG_HEADERS): Make config.h.
* specs/specl_spec.lua: Move from here...
* specs/specl_spec.yaml: ...to here. Reformat to yaml.
* src/specl.mk (check-local): Move from here...
* specs/specs.mk: New file. ...to here.
* src/specl.lua (run_examples): YAML doesn't provide a pleasant
way to format reserved descriptions (before, after) outside of
the ordered list of actual examples, so we have to make a first
pass over the list to extract them, and then be careful not to
run them again in the main loop.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
specs: a minimal environment sharing spec.

* specs/environment_spec.yaml: New file. Ensure before, after,
examples in the same scope share execution environments
correctly.
* src/specl.mk (specl_SPECS): New macro. List all spec files.
(EXTRA_DIST): Adjust.
(check-local): Add dependencies. Remove unnecessary environment
setting. Pass a static list of spec files.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
specs: factor out specification checking to a separate makefile.

* src/specl.mk (Specs): Move this section from here...
* specs/specs.mk: New file.  ...to here.
* Makefile.am: Include specs/specs.mk.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
configury: user-overridable search for install libyaml.

* configure.ac (AC_CHECK_HEADERS): Look for yaml.h.
(AC_SEARCH_LIBS): Abort with an error if libyaml is not found.
* yaml/yaml.mk (yaml_lyaml_la_LIBADD): Remove hardcoded -lyaml.
* specl-rockspec.lua (external_dependencies): Add yaml.
(build.build_command): Pass through YAML options from rockspec
make command.

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