- update plugins.conf for new parametrs of mod_logging.so

doc/plugins.conf

@@ -2,8 +2,9 @@
 # file={path for DB file with user auth information}
 plugin /var/lib/uhub/mod_auth_sqlite.so "file=/etc/uhub/users.db"
 
-#
-plugin /var/lib/uhub/mod_logging.so
+# log subsystem.
+# file={/path/to/logfile} 
+plugin /var/lib/uhub/mod_logging.so "file=/var/log/uhub.log"
 
 #
 # plugin /var/lib/uhub/mod_auth_simple.so