Some of our tests checked for exceptions using an error-prone
try block: they allowed the expected exception to pass, but sometimes
forgot an else block, so the test passed when an exception wasn't
thrown.

This changes the tests to use the appropriate nose tools (raises,
assert_raises).
For consistency, tests that had a correct else block are also changed.

Also fix some test problems that were hidden by the above:
- in some sudorule and HBAC tests, change the *_add_user argument name
  from `users` to `user`
- don't remove HBAC testing data while it was still used

The ipaldap.py code was updated to consider the schema when making
changes and does a REPLACE on single-value attributes. So when you
do an add in an update it will effectively replace the value instead
of ignoring it.

The changes include:
 * Change license blobs in source files to mention GPLv3+ not GPLv2 only
 * Add GPLv3+ license text
 * Package COPYING not LICENSE as the license blobs (even the old ones)
   mention COPYING specifically, it is also more common, I think

 https://fedorahosted.org/freeipa/ticket/239

We dropped the schema for ipaContainer so use nsContainer instead.

ticket 121

In order to run the tests you must put your DM password into
~/.ipa/.dmpw

Some tests are expected to generate errors. Don't let any ERROR
messages from the updater fool you, watch the pass/fail of the nosetests.