* data/bison.m4 (b4_percent_define_flag_if): Don't treat 0 as false.
Complain if the value does not match empty, "true" or "false".
* data/c++.m4: Adjust default definitions of %define variables.
* data/java.m4: Adjust default definitions of %define variables.
* doc/bison.texinfo (Decl Summary): Adjust the %define entry according
to above behavior.
* tests/input.at (Boolean %define variables): Test new behavior.
* NEWS: Mention java.
* TODO: Remove things that are done.
* bootstrap.conf: Add javacomp-script and javaexec-script.
* configure.ac: Invoke gt_JAVACOMP and gt_JAVAEXEC.
* data/Makefile.am: Add new files.
* data/java-skel.m4: New.
* data/java.m4: New.
* data/lalr1.java: New.
* doc/bison.texinfo: Put "A Complete C++ Example" under
C++ Parsers. Add Java Parsers. Put C++ Parsers and Java Parsers
under Other Languages.
* src/getargs.c (valid_languages): Add Java.
* src/getargs.h (struct bison_language): Update size of string fields.
* tests/Makefile.am: Add java.at.
* tests/atlocal.in: Add CONF_JAVA and CONF_JAVAC.
* tests/java.at: New.
* tests/testsuite.at: Include it.