Add extra error handling for creating vlans

[matt852]

For cases where there is an Exception thrown when trying to retrieve device tags, I added in exception handling to ignore the tags and continue processing the vlan creation.

This resolved the issue when I tested it locally, however it does not necessarily resolve the root cause of the issue, which I believe stems from the device.get_device_tag_id() method further upstream.

[matt852]

Closes issue #280