update to 5.0, some feature enhancements

i really like this theme, and am using it on a site, so i decided to upgrade it to 5.0. on the way, i ended up tossing in a few new features and doing some basic code cleanup. apologies for the mega patch! here's what i've done:

• upgraded the necessary components to 5.0
• added options for toggling a site logo, site slogan, and search box
• added a javascript hack that works around IE's deficiency with transparent .png's -- this was necessary to allow a usable site logo. the feature requires a .js file which i placed in the same directory as the theme file--i'll attach it to a comment here for addition to the repository
• separated the site name out into it's own div to increase themability via css
• added some css classes for the page title and the breadcrumb
• wrapped the node taxonomy links with the user and date info, so that it can be displayed/hidden as a unit
• small edit to the display of the headerlinks class -- it now displays the delimiter on both sides of the items as well
• removal of white space
• various small code cleanups

although i'm a fairly experienced module/core coder, this is my first real work in the theming area. i asked for help where i thought it necessary--hopefully i haven't screwed things up too badly... :)