[Ecls-list] Xmas fixes

[Juan Jose Garcia-Ripoll]

Finally the Xmas were more distracting than I hoped, and some issues raised 
about pathnames made me forget some more appealing projects. These are the 
changes to ECL after these weeks (available in CVS):

+ Fixes in the routines that deal with pathnames and access the filesystem: 
they now merge all pathnames with *DEFAULT-PATHNAME-DEFAULTS* and thus it is 
possible to use this variable as a sort of lisp current working directory.

+ New function SI::GETCWD returns the current working directory of the C 
library.

+ SI::CHDIR now takes a boolean as a second argument:
	(SI::CHDIR new-directory &optional update-d-p-d)
If update-d-p-d is true, then *DEFAULT-PATHNAME-DEFAULTS* takes is set to the 
truename of the new working directory.

+ Pathname versions are now properly handled and printed. At least for logical 
pathnames, because physical namestrings cannot have version numbers.

+ An error is signaled when one tries to print _readably_ a pathname that does 
not have a namestring such that parsing this namestring produces the same 
pathname. This happens, for instance, with pathnames that do not have hosts, 
or that have version numbers and are not logical.

+ Various fixes in the CLOS subsystem. The most important is that ADD-METHOD 
and REMOVE-METHOD now update the GENERIC-FUNCTION slot of method objects, and 
output the right values.

+ It is now possible to use two nested SYMBOL-MACROLET that define the same
symbols.

Regards,

Juanjo