overhaul of the category display: it is now able to display multi-level deep categories, use cattree.css instead of mktree.css for a more dense display of the category tree in tree style (see category-procs.tcl for the whole path).
improved category display (faster, much less SQL queries, tree-style and plain style, opening tree automatically for a specified page), improved and unified CSS and JS handling (requireCSS and requireJS)