[uiprops] use lazystr and update some variables usage in css to get a chance to change style without having to change all properties. Also had missing boxHeader.png file (formerly header.png).

\.svn
^build$
^dist$
\.pyc$
\.pyo$
\.bak$
\.old$
\~$
\#.*?\#$
\.swp$
^doc/book/en/apidoc$