These plurals (e.g. "gateau" -> "gateaux") were added to makeplural and
makesingular in 0c0262e, so the test was outdated and failed. I also
added another test for "Federal Bureau of Investigation", since 'bureau'
is an exception to the -eau rule (pluralizes as 'bureaus') and the
exception was originally implemented in a way that would have caused the
"Federal Bureau of Investigation" test to fail -- so it seems like a
good pitfall to test for.