Config fixes for Ubuntu 14.04

Apache now expects sites-[available|enabled] to end in .conf, so update dev creation to create 000-default.conf instead of [000-]default.

Gearman no longer creates a PID file that can be checked for. Instead, check the status directly by asking gearadmin for the PID.

refs #7293
Similarly, can be shortened to:

```sh
gearadmin --getpid || exit 1
```