(Bug 4362) Add header links to Planet Caravan
-- Use props
-- Rephrase prop desc for clarity and consistency
-- Add CSS
-- Remove redundant CSS; remove tab
-- Change priority order so current works
-- Add props in themes
-- Use page_title for _link
-- Use module colors if any
Merge pull request #590 from ninetyd/bug4362/pc_header_links

(Bug 4362) Add header links to Planet Caravan