1) Introducing support for 32/64-bit variants of the patch files
2) Fix bug in fix_epoc32_linux.pl whereby changes to the gcc -preinclude patch file were not applied if already existed.
3) Extending weed_backups.pl to weed the epoc32 tree as well as the package dir
4) Make build_target.pl return non-0 if build has warnings
5) Make build_all.pl fail a target if it has warnings
(binary:application/java-archive)