New Autotest testsuite option --recheck.
* lib/autotest/general.m4 (AT_INIT): New variable $at_recheck.
Escape hyphen in $at_dir early. Accept command line switch
--recheck. Set $at_suite_log early, based on --directory
switch; with --recheck, include the list of FAILed and XPASSed
tests from old testsuite.log file in $at_groups. Document
--recheck in --help output.
* tests/autotest.at (recheck): New test.
* doc/autoconf.texi (testsuite Invocation): Document --recheck.
* NEWS: Update.
Signed-off-by: Ralf Wildenhues <Ralf.Wildenhues@gmx.de>