maven.ui.navcol.width has no effect

According to the docs, when using the "classic" theme, maven.ui.navcol.width should control the width of the nav column. The width is now hard-coded to the default (20%).

I am attaching a patch that fixes the problem for the examples that I have looked at. I am not a css expert, so it is possible that the patch has other side effects that I do not know about. Pls review carefully before committing, or replace with a better fix. Thanks!