This commit changes the behavior of Bison on when used with -o foo_tab.c. Before, it would create foo.output, recognizing that _tab is the same as .tab, and therefore should be omitted, now it would create foo_tab.output. In other words, I don't think that, today, our Unix platforms should care about foo.tab.c not being valid on M$ DOS.
But I'll wait for a go before installing.
