[22.4] How to ENTMAKE a Block Complex Entity in AutoLISP


   See http://xarch.tu-graz.ac.at/autocad/stdlib/ENTMAKE.LSP or 
   http://www.autodesk.com/support/techdocs/td30/td301515.htm (broken)
   There is an example how to use multiple calls to (entmake) to create
   the block header, the entities, closes the block and finally
   (entmake) the INSERT.
     For anonymous blocks beware that only
   (setq bn (entmake '((0 . "ENDBLK")))) returns the blockname for
   (entmake (list '(0 . "INSERT")'(70 . 1)(cons 2 bn) ...))