Experimental ESXi Support

I saw feature 41 on redmine and thought I'd share a MachineManager I wrote to handle the malware VM within an ESXi environment using the python module pysphere. It's an early build but I'm working to add more validation and handling around power state and snapshots. I'd love to finish it and contribute to Cuckoo. 

It supports power state, snapshot rollback, and network analysis. To use network analysis, create a vSwitch for your cuckoo box and VM's. Add a network interface for each VM and IP them for a private network. 

Example: 
```
Cuckoo Master:
IP: 10.2.2.1
Netmask: 255.255.255.0
GW: None

Malware 01:
IP 10.2.2.10
Netmask: 255.555.255.0
GW: None
```