New Complex modules

[Mike Griebling <grieblm@trt.allied.com>]

I've updated the Complex modules to add constructors for the COMPLEX numbers
and also added some query routines to return the real and imaginary parts of
a COMPLEX.  Finally, I've added several conversion functions to LONGCOMPLEX
called Short and Long which convert LONGCOMPLEX to COMPLEX and vice versa,
respectively.

The best way of dealing with COMPLEXVECTOR types will be to define a new
module which is independent of the existing COMPLEX functions.  This new
module will have to define some routines which accept a COMPLEX/LONGCOMPLEX
number and initialize an array element and extract that value from an
array index.  Other vector-based operations would also be placed in this
module (ie. vector slices, copies, scalar multiplies, additions, etc.).  If 
someone would like to define such a module -- please do so.  I won't be
able to since I'm working on the PPC back-end at the moment.

Michael G.