Update vnu-jar to the latest and greatest

[Daniel Brommer]

Hi,

I would love to use the option --exit-zero-always which is available since vnu-jar 17.2.1

Would you accept a pull request ?

Cheers, Daniel.

[Daijiro Wachi]

@DanielBrommer Hi, patches are always welcomed! I'd love to merge it when you create PR :)

You may want to update the version of this line to the latest: https://github.com/watilde/gulp-html/blob/master/package.json#L30

[Daijiro Wachi]

The latest version is 17.3.0.