Add vsock support

[guillaumerose]

The cid address should be a parameter or auto.

With a fixed cid, when I try to run 2 VMs, I obtain the error:

ERRO Error creating machine: Error creating the VM: Error creating machine: Error in driver during machine creation: virError(Code=38, Domain=0, Message='failed to set guest cid: Address already in use') 

[praveenkumar]

The cid address should be a parameter or auto. When I try to run 2 VMs, I obtain the error:

@guillaumerose In this PR cid is set to auto so does trying of 2 VM's still fails?

[guillaumerose]

I double checked and it's fine with auto.

I had to fix a path in the driver for running multiple crc instances: #48

[praveenkumar]

👍