CLI can show VTEP configurations.

- Can display full configuration info such as connection state.
- Can list all the bindings for a VTEP.

Sample CLI command lines:

midonet> vtep list
name br0 management-ip 119.15.112.22 management-port 6633 connection-state CONNECTED
midonet> vtep management-ip 119.15.112.22 list binding
management-ip 100.100.100.1 physical-port port 1 vlan 201 network-id ca07e054-2cef-4b6e-8d0a-c3b8e747615b
management-ip 100.100.100.2 physical-port port 2 vlan 202 network-id 60e94be7-276b-4eec-a845-f16671f01467

Fix MN-1638
Merge pull request #166 from midokura/dev/tomohiko/vtep-cli-mn1638/201405161837

CLI can show VTEP configurations.