For Z 39.50 Stuff

pageaction.cpp
--------------
Macros:
 * for "about" page, use a custom _textbrowseoptions_ macro (ie
   create a new macro, maybe create a z3950.dm macro file ??)
   (also maybe _numbrowseoptions_

(Irrelevant?) (c. line 332)
    disp.setmacro ("numdocs", "Global", cinfo.numDocs);
    disp.setmacro ("builddate", "Global", builddate);

That message "This collection contains..." is in the _collectionextra_
macro.
could get numdocs from the z39.50 server, as well as any other status
information.

win32.mak
---------
Needs updating for all added files (z*, parse.fl)

yaz
---
Maybe put libyaz.a in $GSDLHOME/lib ?


DESIGN ISSUES
for z39.50 (and eventually nullproto when corba allows recept. and
coll server to be physically separate), if the server is unavailable,
should this be determined at:
  * "home page" creation time, in which case the recept. must ping and
test each collection it knows about, which may cause unacceptable delay, or
  * "about page" creation time (ie individual collection), in which case
the collection can not customise the page layout by modifying macros.

Eg currently, the z39.50 collection will not create a TCP connection to the
"target" (ie z39.50 server somewhere around the world) until it tries to
get the "About this collection" information for that collection. 
If the connection fails, the protocol can not change _queryform_ part of
the page.


MULTI-LINGUAL SUPPORT
Multi-lingual - eg macros - want to set _collectionextra_ using
metadata["collectionextra"] based on the chosen interface language.
Should be done by OIDtools.cpp:get_info() and any action that calls
proto->filter().
queryaction.cpp (c. line 1097):
  // add the requested language as an option to the query
  if (!args["l"].empty()) {
    OptionValue_t option;
    option.name="Language";
    option.value=args["l"];
    request.filterOptions.push_back(option);
  }

