Cleanup the "other content" dropdown

Here's how to fix it:
a) Get some prettier css.
b) do a "select distinct type from node" to get all nodes that have been created on the site (while filtering out non-content node types) to get the current list of content types of the site. Cache the query for a few hours as well so we're not running this query on every page load.

Define our little drop-down box as a block and just print the "Browse by type of content" right into the page.tpl.php file.

Changed my mind again. The items should just be added as a nav bar along the top. Keep things simple.

Committed a fix for this task (along with a lot of other css) tonight.