Add "facts" properties to ASA and AireOS

[jmcgill298]

Both AireOS and ASA device classes need to implement properties that were previously associated with facts:

ASA:

• [x] vendor
• [x] uptime
• [x] uptime_string
• [x] hostname
• [ ] fqdn
• [x] interfaces
• [x] vlans
• [x] model
• [x] serial_number
• [x] os_version

AIREOS:

• [x] vendor
• [x] uptime
• [x] uptime_string
• [x] hostname
• [ ] fqdn
• [ ] interfaces
• [ ] vlans
• [ ] model
• [ ] serial_number
• [ ] os_version