[Ecls-list] Fix for tilde expansion

[Juan Jose Garcia-Ripoll]

 - When expanding tilde pathnames, as in "~/bin/foo", the device is also
   taken into account. So if HOME=c:/jjgarcia, the previous path becomes
   "c:/jjgarcia/bin/foo"

 - If the homedir component contains a tilde itself, ECL entered an infinite
   loop when expanding the pathname

My fix is based not on strings but on MERGE-PATHNAME, which is more
robust and allows for further information (hostname, device, file
type, etc) on the home directory.

Juanjo

-- 
Facultad de Fisicas, Universidad Complutense,
Ciudad Universitaria s/n Madrid 28040 (Spain)
http://juanjose.garciaripoll.googlepages.com