added jQuery function to append header to #header tag

moved display ad function further down the main file
ad is no longer displayed in admin area, only on front page

and as a preview in the admin interface of course
tweaked CSS
header ad works great - but can't post with P2 anymore :-(
added main function to wp_head

tweaked heigh depending on use of header image
added funky fade-in effect
called display ad with get_footer hook instead of wp_head

this fixes an issue with Firefox when archive pages are displayed
Merge branch 'jQuery'