Update commoner to 0.8.8 for Windows support

benjamn/commoner#44 fixed commoner to work on Windows when module path relativization isn't used; with this, the `jsx` binary should work properly on Windows (though `jsx-internal` still won't).

Fixes #316, fixes #391, fixes #567.
Merge pull request #601 from spicyj/commoner-088

Update commoner to 0.8.8 for Windows support.