notes on heh-g and h

[Hugh Hoover <heh>]

I forgot to put the note at the start of these files... sorry.
(it's more trouble to change them than to send a mail message...)

-g:
  a) Changes to tapestry - enhancements for link maker window
  b) fix to smalltalk compiler - it incorrectly set sourcePosition
     for constants (like true and false).  This caused the error
     message stuff to bomb in a wierd case (unused variable set to false).
  c) minor changes to text stuff
  d) major changes to PortionListComp - rewrote space allocation
     algorithm (computeExtents) so it will work correctly with upperbounds
  e) changed spec of Portion to use a region instead of two
     integerVars.  This allows for infinite upperbounds.

-h:
  a) changed spec of PortionListComp to use a ListModel of Portions
     rather than a scruTable.  I did this because the PLC must be
     a dependent of the list and tables should no longer be XuModels.

--Hugh