scli vlan detail: gracefully handle hardware that has no name/domain

[flavio-fernandes]

BUG: #996

Avoid exceptions in cases when IMS returns hardware or VSI instances
that have no 'hostname' and 'domain' attributes.

An example of such:

$ slcli vlan detail 1499927
An unexpected error has occured:
Traceback (most recent call last):
  File "/home/vagrant/.venv/local/lib/python2.7/site-packages/SoftLayer/CLI/core.py", line 176, in main
    cli.main(**kwargs)
  File "/home/vagrant/.venv/local/lib/python2.7/site-packages/click/core.py", line 697, in main
    rv = self.invoke(ctx)
  File "/home/vagrant/.venv/local/lib/python2.7/site-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/vagrant/.venv/local/lib/python2.7/site-packages/click/core.py", line 1066, in invoke
    return _process_result(sub_ctx.command.invoke(sub_ctx))
  File "/home/vagrant/.venv/local/lib/python2.7/site-packages/click/core.py", line 895, in invoke
    return ctx.invoke(self.callback, **ctx.params)
  File "/home/vagrant/.venv/local/lib/python2.7/site-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/home/vagrant/.venv/local/lib/python2.7/site-packages/click/decorators.py", line 64, in new_func
    return ctx.invoke(f, obj, *args[1:], **kwargs)
  File "/home/vagrant/.venv/local/lib/python2.7/site-packages/click/core.py", line 535, in invoke
    return callback(*args, **kwargs)
  File "/home/vagrant/.venv/local/lib/python2.7/site-packages/SoftLayer/CLI/vlan/detail.py", line 76, in cli
    hardware['domain'],
KeyError: 'domain'

Feel free to report this error as it is likely a bug:
    https://github.com/softlayer/softlayer-python/issues
The following snippet should be able to reproduce the error

[coveralls]

Coverage increased (+0.04%) to 88.554% when pulling de7c255 on flavio-fernandes:vlan_detail_bug.merge into 6332ffe on softlayer:master.