Started refactoring the command shell.

The existing code has a lot of redundancy.
A few misc fixes.
Started some unit tests.

This is still very incomplete. Also, one of the tests is only
half-written, and is thus failing.
Added some code to change vlans via serial (powerconnect)

It isn't currently integrated into the rest of the codebase. Preliminary
interactive testing suggests that it works.
A bit more work on the dell serial driver

It's integrated with the rest of the haas, though hasn't really been
tested that way; the haas master doesn't have VT, and this is causing an
exception to be thrown before we get to invoking the driver.
Changed the config to match our current setup.

Really, this shouldn't require a commit; see issue #17. Until we fix
that though, This is what we'll have to do.
Updated copyright date.
Merge branch 'devel' into dell-serial
Merge remote-tracking branch 'origin/devel' into cli-refactor
cli refactor done
Update haas_shell.py
update
added the missing create_headnode
Wrote a test concerning duplicate vlans.

Currently the test is failing.

In addition, I added a docstring to the other test.
duplicate vlan test is now passing.
test_exist
- got rid of redundant copy of help message text
- modified help text to put items that operate on same object near each other
  in message
merging back from cli-refactor after modifying help messages
Merge branch 'cli-refactor' of github.com:CCI-MOC/haas into cli-refactor
- added space after prompt for user name