Add information about the dmenu requirement.

Thanks <surfsup@inbox.lv>!
Add a FAQ to surf.
Fix the manpage about xid.

Something was missing from this one sentence. Now it is complete.
Mention xdotool in SEE ALSO too.
Make »Copy image address« work.

Thanks yui@blekksprut.net for the patch!
Minor style change.
Merge remote-tracking branch 'upstream/master' into patches
add per-site user styles

since the css domain selectors do not work in webkit, another approach needs to
be taken to support custom css for specific sites. In config.h there is now a
list of regexes and corresponding css filenames. When a page is loaded and
userstyles are active, the first entry that matches the uri is used as
user-stylesheet-uri. The old static stylesheet is removed but can still be used
by installing a default rule matching any site at the end of the list.