Change category field cardinality to 1

This feature has the ability to sort content by weight. Giving the
category field unlimited values makes it impossible to manage sorting
per category.
Add weight settings to content type
Add the knowledge-base/ landing page

This provides the landing page menu item, meun callback, and template
file for the knowledge base home page. Everything in this page should be
extensible by the theme layer with standard Drupal theming techniques.
Order field definitions by alpha to make Features chill out
Add pathauto patterns for content and terms
Add search views view page with exposed block form