pgsql: Man pages back to lowercase names, with additional fixup to make

Log Message:
-----------
Man pages back to lowercase names, with additional fixup to make the .so
links work.

Modified Files:
--------------
pgsql/doc/src/sgml:
Makefile (r1.116 -> r1.117)
(http://anoncvs.postgresql.org/cvsweb.cgi/pgsql/doc/src/sgml/Makefile?r1=1.116&r2=1.117)