Fix #4345 Privileges editor shows databases with underscore backslash-escaped

Signed-off-by: Ann + J.M <phpMyAdmin@ZweiSteinSoft.de>
Add ChangeLog entry for bug #4345

Signed-off-by: Ann + J.M <phpMyAdmin@ZweiSteinSoft.de>
Finish 4345-privs-dbname-underscore-backslashes