Change authentication error message (patch)

Hello,

Instead of pushing extra info to the logs I decided that we could 
without giving away extra details per policy. I wrote the error message 
in a way that tells the most obvious problems, without admitting to any 
of them. Please see attached:

diff --git a/src/backend/libpq/auth.c b/src/backend/libpq/auth.c
index 415b614..a775534 100644
--- a/src/backend/libpq/auth.c
+++ b/src/backend/libpq/auth.c
@@ -270,7 +270,7 @@ auth_failed(Port *port, int status)                        break;                case uaPassword:
            case uaMD5:
 
-                       errstr = gettext_noop("password authentication 
failed for user \"%s\"");
+                       errstr = gettext_noop("password, username or 
password expiry failed for user \"%s\"");                        /* We use it to indicate if a .pgpass password 
failed. */                        errcode_return = ERRCODE_INVALID_PASSWORD;                        break;