GUACAMOLE-163: Remove DEFAULT CURRENT_TIMESTAMP from guacamole_user's password_date column (compatibility with MySQL 5.5 and older).

extensions/guacamole-auth-jdbc/modules/guacamole-auth-jdbc-postgresql/schema/upgrade/upgrade-pre-0.9.11.sql

@@ -22,7 +22,12 @@
 --
 
 ALTER TABLE guacamole_user
-    ADD COLUMN password_date timestamptz NOT NULL DEFAULT CURRENT_TIMESTAMP;
+    ADD COLUMN password_date timestamptz;
+
+UPDATE guacamole_user SET password_date = CURRENT_TIMESTAMP;
+
+ALTER TABLE guacamole_user
+    ALTER COLUMN password_date SET NOT NULL;
 
 --
 -- User password history