[WIP] Update Ignoracle tests to use wpull 2.0 interface

[hannahwhy]

This PR re-enables the ignoracle tests and ports them to use the Ignoracle wpull 2 interface.

It looks like the tests also caught a bug in the port:

$ nosetests
...........Pattern ??? is invalid (error: nothing to repeat at position 0).  Ignored.
.......Pattern {primary_netloc}{1}/foo\.css\?{} is invalid (error: nothing to repeat at position 0).  Ignored.
F........
======================================================================
FAIL: test_permits_empty_brace_pairs_and_regex_repetitions (archivebot.wpull.ignoracle_test.TestIgnoracle)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/home/trythil/prj/ArchiveTeam/ArchiveBot/pipeline/archivebot/wpull/ignoracle_test.py", line 56, in test_permits_empty_brace_pairs_and_regex_repetitions
    self.assertEqual(result, pattern)
AssertionError: False != '{primary_netloc}{1}/foo\\.css\\?{}'

----------------------------------------------------------------------
Ran 27 tests in 0.057s

FAILED (failures=1)

I'm holding off merging until I can investigate that test failure further.