Switch to CPython list sort(Not its list implementation)

If BoxedList::allocated is -1, it means the items inside were changed.
Some CPython list functions need this to check exceptions.

CPython listsort need "allocated" to check and throw exception:
https://github.com/Daetalus/pyston/blob/d84105ffc8a4855bb6e00d9c22ba2baa8bddf969/from_cpython/Objects/listobject.c#L2091
https://github.com/Daetalus/pyston/blob/d84105ffc8a4855bb6e00d9c22ba2baa8bddf969/from_cpython/Objects/listobject.c#L2180

Comment out some part of listobject.c, use the CPython list sort and
apply some changes to existed Pyston code.

ScopeNameUsage merge dicts into a single big one

and change it to use a unordered_map because it uses less memory in this case and is faster
(I assume because it does not have align the key value tuples)
saves about 10% of peak memory on django

Update to fewer-pyston-changes virtualenv

hidden classes: split into subclasses to reduce memory consumption

+ use pyston::DenseMap to save a little more memory

this saves about 5%-10% of peak memory on django

Fix evaluation order for dict operations

enable `PyObject_Format` in `from_cpython/Objects/abstract.c`

using cpython's `sys.flags` inplementation

Support empty lines on the repl

They end up generating "pass" statements with a lineno of 0, which
trips an assert later on.  This commit just sets them to have a lineno
of 1.

I'm not sure how to test this, since piping into stdin is supposed to
be treated as a file (not as the repl).  Though, we get that wrong right now.

use cpython's abstract.c instead of src/capi/abstract.cpp

generator optimizations

Adds a few C API paths plus sets tp_iternext and tpp_hasnext

Fix extra nonzero call for chained comparisons #1190

long: dealloc gmp memory

Replace None with Py_None and some other fixing.

Pyston already has Py_IgnoreEnvironmentFlag, just add it to sys.flags.

When try to support tk. The Py_None is a wrapper of pyston `None`. It
will conflict with other library's None. So rename the pure pyston
`None` to pyston_None. And use Py_None instead pyston_None when
possible. Just like dropbox#1231 for Py_True and Py_False

add _bisect, always_use_version support CAPI, set some frequent accessed slots

+ fix a leak in PyList_Insert

implement tp_str and tp_repr for more of our builtin types

Have function.func_globals always be dict-like