false check emulation light (CEL) warnings for service validate using pidof

```
Run a scenario observe the CEL warning in the bottom right.

"DATE: Tue Oct 1 07:09:01 2013
LEVEL: ERROR (2)
NODE: 2 (n2)
SESSION: 41413
SOURCE: service:OSPFv2

validate command failed: pidof ospfd"

The pidof validate command is invoked before the quaggaboot.sh script has a
chance to launch the ospfd service.

This happens with many of the "pidof" validate commands.
```

Original issue reported on code.google.com by `ahrenh...@gmail.com` on 1 Oct 2013 at 2:42