object file for som v1.7

for t-code, globals are in M65..M255.  They must be stored in the "snapshot" too.  So, in the object file, globals must be stored.  This is additional (**) to the original object file.  The new object file is as follows:

magic
begin end 
code segment (in hex)
** begin end 
** globals (in hex)
begin end
data segment (in hex)
size
symbol table

We also use hex number instead of decimal as to avoid negative number and it is more natural to inspect the code segment in hex.

5 June 2006
