Known Issues:
* find'ing something 3 times, should not return three different nodeset thingis
  (i suppose this is not possible)
* when clearing (aka deleting) the nodes in a nodeset thingi, all other nodeset thingis
  referencing the same search have still access to the nodes, and can therefor crash the whole
  thing bad
* same goes for attributes, nodes, attributeset you got from some nodesets you deleted afterwards

Solutions:
* don't save the nodeset, save the actual nodes
* register each node (attributes and elements) in an array in the rbxs_base
* delete should be an operation of each node

This is internal an should help garbage collecting, IT WILL NOT CHANGE THE API.

Todo:
* add a way to move nodes inside the document, and copy them between components
* add apply_style to dom (apply xslts) - keep in touch with Ken Wronkiewicz <wh at wirewd dot com> 
  who is interessted  in this
* finish pull parser
* add a way to dom from strings read-only and write
* create detailed documention, not only examples