slingshot: adopt slingshot release mechanism.

* README: Move from here...
* README.md: ...to here. Adjust for GH Markdown.
* GNUmakefile, Makefile.am, build-aux/mkrockspecs,
m4/ax_compare_version.m4, m4/ax_lua.m4:
Remove. These files are handled by slingshot now.
* rockspecs.lua, m4/ax_with_prog.m4: Remove. No longer used.
* bootstrap.slingshot: New file. Slingshot bootstrap plugin.
* bootstrap.conf: Source it.
* configure.ac: Adjust to drive slingshot processes.
* local.mk: New file. Project local make rules.
* rockspec.conf: New file. Slingshat rockspec template.
* specs/specs.mk: Simplified.
* .prev-version: Record previous version number.
* .gitignore: Update.
* .travis.yml: Regenerate.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
specs: convert lunit fcntl checks to specl specs.

* README: Remove reference to lunit.
* tests-fcntl.lua: Remove.
* specs/posix_lua_spec.yaml: New file with equivalent checks for
Specl.
* specs/specs.mk (specl_SPECS): Add specs/posix_lua_spec.yaml.
* local.mk: Include specs/specs.mk.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
specs: convert adhoc tests to specl specs.

* tests-curses.lua: Remove. Move contents from here...
* specs/curses_spec.yaml: New file. ...to here, and reformat.
* tests-posix.lua: Remove.
* specs/posix_spec.yaml: New file. Implement equivalent (or
better!) specs here.
* specs/specs.mk (specl_SPECS): Add new specs.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
specs: fix some spec failures on Linux.

* specs/posix_spec.yaml (uname): uname -a can display information
that uname(2) does not return, so change the command to say
explicitly what fields we want.
specs: ttyname can contain 'pts' rather than 'tty'
maint: collect previous release notes into NEWS.

* NEWS: New file, required for the Slingshot release process.
* local.mk (old_NEWS_hash): Update.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
syntax-check: fix many tiny errors raised by sanity.mk.

* config.ld: Remove trailing blank line.
* lcurses.c, strlcpy.c: Remove useless preprocessor parens.
* lcurses.c: Use the blessed `#include <config.h>` format.
* local.mk: Remove leading space from SPACE-TAB sequence.
* lposix.c (STREQ): Define to avoid using inverted strcmp logic.
Also remove useless preprocessor parens, and trailing whitespace.
* posix.lua, specs/posix_spec.yaml: Remove trailing whitespace.
* specs/posix_spec.yaml: Use 'file system' in preference to
.filesystem'.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
sanity: add configuration fragment with sanity exclusions.

* build-aux/sanity-config.mk (sc_require_config_h)
(sc_require_config_h_first): Exclude dummy.c and strlcpy.c, which
are both included directly into another source file before
compilation.
* .gitignore, build-aux/.gitignore: Adjust.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
configury: bump release version to 29.

* configure.ac (AC_INIT): Bump release version to 29.
The '5.1.' prefix is a misnomer now tha we support Lua 5.2, and
bumping the prefix to '5.2.' would be no better, since we support
Lua 5.1 simultaneously, and 5.3 will be along one of these days.

Signed-off-by: Gary V. Vaughan <gary@gnu.org>
specs: add pending guards to weird Travis failures.

* specs/posix_spec.yaml: Mark pending those examples inexplicably
failing on Travis, per github issue #102.

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