[development] FYI more drupal.css stuff

[Khalid B]

> On my servers i have ~20% recurring visits and ~80% one-time visits. So for me it
> would save 30%*80% = 24%.

This is something that I observed a long time ago. CSS is often a
large part of my
web sites' bandwidth usage. I wrote about that

One site has .css files taking 10.5 % of the hits, yet 19.6 % of the bandwidth.

Another site with a different theme has .css as 11 % of hits, and 13.6
% of bandwidth. That site has more css that the first one, since it
uses event module which emits its own css.

Both sites have the css compressed, although I remember the latter one
having an issue with the compressed version, so I reverted back to the
normal version.

I forgot about drupal.css. I will compress that next, and copy it.
Thanks Piotr for the reminder.