booth-check-clone.pl script to be used as 'before-acquire-handler' in booth

booth-check-clone.pl script to be used as 'before-acquire-handler' in booth


Example:

```
# cat /etc/booth/booth.conf
transport="UDP"
port="6666"
arbitrator="172.16.6.30"
site="172.16.6.31"
site="172.16.6.32"
ticket="ticket"
  expire = 120
  before-acquire-handler = "/usr/local/bin/booth-check-clone.pl ms_MySQL"
```