.hgignore missing webrevs?

[Bradford Wetmore]

I've noticed in various repos that the .hgignore files include 
variations on webrev, ^webrev/, or leave it out completely.  In other 
words, it's inconsistent.

Mark offered:

 
http://mail.openjdk.java.net/pipermail/build-dev/2008-February/000742.html

which add your own personal .hgignore file, but that means everyone has 
to do it.  Would a simple cleanup of webrev/.hgignore be a good idea:

+ ^webrev/
+ ^webrev.zip

Brad