Hardening/43 password in log file

### Description
Removed clear-text password from log messages.
Fixes issue #437 

What about?

```
LM_E(("Database Startup Error (authentication: db=admin, username=%s: %s, paswd=*****)", username, err.c_str()));
```

It gives the notion that a password field was used... and, at the same time, fulfills the requirement on not showing it in clear text.