libpq++ uses fe_setauthsvc which is deprecated and results in an error

  libpq++ uses fe_setauthsvc which is deprecated and results in an error
on connection. This patch changes it to use PQconnectdb rather than
{fe_setauthsvc,PQsetdb}. This still isn't the complete solution, as
there
is no provision for user,password in class PgEnv, but it does get rid of
the error message. Tested with gcc version egcs-2.91.60 19981201
(egcs-1.1.1 release) under NetBSD-1.3K/i386.

Cheers,

Patrick Welche