misc library work

Paste kind of uses it.

It might also be ok to just have it throw an ImportError()

This gets pycurl and PIL working.

Unfortunately I can't figure out a great way to test this; pycurl
has external dependencies, and PIL only works with some workarounds
that I don't want to check in.  I think these features are
innoccuous enough that it's worth getting these in.

Surprisingly, setting tp_getattr and tp_getattro have pretty different behavior;
we can kind of make tp_getattro work with subclassing but apparently don't
do very will with tp_getattr.

Punt on fixing that for now and switch thread._local to use getattro

Class slot handling is getting pretty messy

Don't pass path to this version of find_module (unlike finders in meta_path).

Implement built-in input() function.

Fewer StopIteration exceptions

Add support for METH_OLDARGS and list.pop(long)

the tpp_hasnext/__hasnext__ changes require us to be able to __call__ descriptors for wrapped pyston methods.  this shouldn't be a problem, though, at least for tpp_hasnext

also advance generators in __hasnext__ so we can return false instead of throwing StopIteration if the generator exits.

Update virtualenv to a version which removes a lot of old pyston specific hacks

Sqlalchemy tests2

We would keep on adding the same object to the weakrefs list,
which would eventually trigger a collection, and cause all sorts
of weird things to happen.

This isn't just a performance optimization, but is actually important
since people put things in dicts that don't __eq__ themselves.
The common example (and test here) is NaN, but in particular sqlalchemy
does this with clauses (where __eq__ returns a new sql clause).

Also, handle cases that __eq__ returns non-bool

And add set.difference_update() and set.isdisjoint()

Using their test runner is quite hard since it tries to override a lot
of basic functionality (ex for enhanced tracebacks).  So just do some
manual test discovery, and only run the tests that cpython can pass
using this setup.

We still fail a couple more though.

Clean up the BoxedTuple class

Fix "sys.excepthook is missing" warnings

Add more imp.* functions, set correct module.__file__, import * with non module globals

Get `cpython/test_property.py` to pass

by adding sys.excepthook.

Add pyxl hello world integration test

Add support for weakref.proxy

add imp.is_builtin, imp.is_frozen, imp.new_module, support object.__hash__(arg), don't always set module.__file__