[AC sjt-xft] Fix crash, update configure.ac, suppress some excessive warnings

APPROVE COMMIT sjt-xft This patch improves Xft support a little - fixes a crash when a strikeout face is encountered - fixes a problem with computing the extent covered by text in tab controls - fixes the --without-mule build bug - enables debug output for the metacity maximize bugfix (this is not a feature and should go away soon) - fixes some bugs in handling non-ASCII charsets (still quite broken, though) - adds a few new debug output, but mostly reduces verbosity significantly and add autoconf 2.59 support - integrates Malcolm's patch - adds AC macro support for "complex options" like --with-sound and --with-athena (currently only used for --with,xft, though) - fixes a few bugs (assignments of the form `eval "$var = $var"') - traps --with-mule and recommends use of --enable-mule - adds a case and some code to regressiontest.pl, which is now parked in tests/autoconf - describes the autoconf 2.59 support briefly in INSTALL It is missing a fix for the problem Ben reported, though. Patch omits configure, and is gzipped for brevity and to armor against the mail-eating bug. -- Graduate School of Systems and Information Engineering University of Tsukuba http://turnbull.sk.tsukuba.ac.jp/ Tennodai 1-1-1 Tsukuba 305-8573 JAPAN Economics of Information Communication and Computation Systems Experimental Economics, Microeconomic Theory, Game Theory