Add sudo option to cron target

This cron task fails on some servers whereas the cron location is for root users only. Even reading the directory is impossible and thus the phing target fails;

```
[phingcall] No read access to /etc/cron.d
       [if] Error in IfTask
Execution of target "cron-deploy" failed for the following reason: Execution of the target buildfile failed. Aborting.
[phingcall] Execution of the target buildfile failed. Aborting.
```