specs: compatibility with Specl < 11.

* specs/specs.mk (specl_SPECS): Move std_spec.yaml to the end of
the list, where symbol leaks don't affect subsequent examples.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
specs: remove duplicate examples.

* specs/math_spec.yaml: forgot to remove the old namespace
corruption tests from this file when adding new check in 3507e84.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
specs: make sure hell.spawn uses the same Lua as Specl examples.

* slingshot: Sync with upstream, for build-aux/specs.mk fix.
* configure.ac (AC_CONFIG_FILES): Add specs/spec_helper.lua.
* specs/spec_helper.lua: Move from here...
* specs/spec_helper.lua.in: ...to here.
* .gitignore: Add spec_helper.lua.
* specs/specs.mk (SPECL_ENV): Add $builddir/specs to LUA_PATH
for generated spec_helper.lua.
* specs/spec_helper.lua.in (LUA): Don't dig through `_G.arg`,
wait for configure substitution.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
Release version 37

* NEWS: Record release date.
maint: post-release administrivia.

* configure.ac (AC_INIT): Bump version to 38.
* NEWS: Add header line for next release.
* .prev-version: Record previous version.
* ./local.mk (old_NEWS_hash): Auto-update.

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