Update the itcl/itk from 3.2 to 3.3 (released in April 2005). The
installed libraries are now named libitcl.so.3 & libitk.so.3 instead
of having the version be part of the libname (libitcl33.so.1). The
itclConfig.sh and itkConfig.sh are now also installed, which is required
by some software (such as the insight -- a gdb frontend).

Fix-up the (unchanged) iwidgets port to reflect the above and improve it
to not require its own copy of the itcl tree at install time.

Approved by: maintainer

Fix-up the tkdesk port to reflect the itcl/itk changes, which required
updating it to the 2.0p2 (from 2.0). (This lovely piece of software
badly needs a caring maintainer, BTW.) While here, teach tkdesk to use
installed blt instead of building its own.

The only iwidget/itk/itcl consumer that remains broken is net/smm++ (a
MUD client). This should change as soon as the maintainer get back to
me.