Store PDU data in a class ^.^, remove crap

OMG I'm writing an XML to domain model mapping here... Why doesn't the
whole world just use Mendix? :o)
client: extract _get method, cosmetics

Lots of pages in the web gui use the get action on a specific path in
the internal ACS information hierarchy.
PDU: also collect table labels and header info
Pretty table output for listipdus

sorting of the table can be toggled with the sort command