Changes to allow for documentation translations

Several parties have expressed interest in translating the documentation
or have already done so.  In order to keep these in tree and be able to
build them easily I propose we make the following minor changes in the
doc/ subtree.

For each translation, make a new directory doc/src/sgml-, where
 is a locale type string.  For example, a German translation
would be in sgml-de.  There you copy whatever *.sgml file you want to
translate next.  When building, untranslated files will be picked up from
the "master" sgml/ directory.

Language independent things will go into doc/src/share (stylesheets,
tools, etc.).

The functionality of doc/src/sgml/Makefile will be moved into
doc/src/Makefile.  When you build the documentation, the language you want
is specified via a make variable, e.g.,

doc/src$ gmake postgres.html LANG=de

(Probably not LANG, though, since that might be in the environment.)

I don't have a clue yet how to package this.  It will depend on how it
comes along.

-- 
Peter Eisentraut   peter_e@gmx.net   http://funkturm.homeip.net/~peter