Building GWT on Ubuntu.

After GWT was building, some of the test cases would fail. Most of them would simply exit with empty test logs. Of course this to had nothing to do with GWT. The default installation of Hardy includes libstdc++6 and the firefox libs included with GWT depend on libstdc++5. This was and easy issue to deal with (with some help from ssolka) except for wading through piles of output from ant -debug and junit.showoutput to get the problem to reveal itself.