We generate libs/ardour/revision.cc in debian/rules. Adapt the wscript to parse our custom format. To avoid confusion with any existing .git directory on a packager's machine, disable the git version check and pretend it's a tarball.
The buildds kill the build if they don't see messages in stdout for a long time. Unfortunately, waf defaults to printing such messages to stderr, so ardour takes too long on slower archs. Work around that by printing to stdout.
