Header and Footer
This enables you to put any XHTML code in front and after of the actual board, i.e. you can 'frame' all the board pages.
Both the header and the footer have to contain self-contained well-formed XML in the stable version. That means you can't leave a tag open in the header even if you close it again in the footer. This is a purely technical limitation (hint: the SimpleXML class is used to build the tree internally, so we're talking about construction using nodes, not just strings) right now. The current development version does not have this limitation.