Bug 990417 - Fix the restart operation when the PID file is corrupted

In case when the PID file is corrupted, Apache fails to restart with:

```
(20014)Internal error: Error retrieving pid file run/httpd.pid
```

This patch will check if there is valid PID file when restarting and if not, then execute the 'start' operation. In case when Apache is already running, it fails with meaningful message and automatically fix the PID file. In case when Apache is down, it starts it.... as user would expect when doing 'restart' ;-)