Moving extensions to either quarantine or deathrow.

When a module is moved to quarantine, it means that while we intend
to keep it, it is currently broken or sufficiently untested that it
can't be in the main IPython codebase.  To be moved back into the main
IPython codebase a module must: 

1. Work fully.
2. Have a test suite.
3. Be a proper IPython extension and tie into the official APIs.
3. Have members of the IPython dev team who are willing to maintain it.

When a module is moved to deathrow, it means that the code is either broken
and not worth repairing, deprecated, replaced by newer functionality,
or code that should be developed and maintained by a third party.

IPython/core/iplib.py

@@ -48,7 +48,7 b' from IPython.core.component import Component'
 from IPython.core.usage import interactive_usage, default_banner
 from IPython.core.error import TryNext, UsageError
 
-from IPython.extensions import pickleshare
+from IPython.utils import pickleshare
 from IPython.external.Itpl import ItplNS
 from IPython.lib.backgroundjobs import BackgroundJobManager
 from IPython.utils.ipstruct import Struct

IPython/core/tests/test_magic.py

@@ -79,7 +79,7 b' def test_shist():'
     # Simple tests of ShadowHist class - test generator.
     import os, shutil, tempfile
 
-    from IPython.extensions import pickleshare
+    from IPython.utils import pickleshare
     from IPython.core.history import ShadowHist
     
     tfile = tempfile.mktemp('','tmp-ipython-')