this is an advantage for _PyObject_GC_TRACK
which before compiled to something like this:
        cmpq    $-2, -16(%rdi)
        jne     .LBB0_2
        movq    $-3, -16(%rdi)
        movq    _PyGC_generation0(%rip), %rax
        movq    %rax, -32(%rdi)
        movq    _PyGC_generation0(%rip), %rax
        movq    8(%rax), %rax
        movq    %rax, -24(%rdi)
        leaq    -32(%rdi), %rcx
        movq    %rcx, (%rax)
        movq    _PyGC_generation0(%rip), %rax
        movq    %rcx, 8(%rax)

and now compiles to
        cmpq    $-2, -16(%rdi)
        jne     .LBB0_2
        movq    $-3, -16(%rdi)
        movq    _PyGC_generation0(%rip), %rax
        movq    %rax, -32(%rdi)
        movq    8(%rax), %rcx
        movq    %rcx, -24(%rdi)
        leaq    -32(%rdi), %rdx
        movq    %rdx, (%rcx)
        movq    %rdx, 8(%rax)

notice that it had to load _PyGC_generation0 three times because the compiler had to assume that because of aliasing it got motified.
(and this loads actually showed up in profiling as somewhat expensive)

tuple: implement tp_as_sequence->sq_contains

Some cleanup for the refcounting merge

enable sqlalchemy_smalltest

I did not trigger this bug (also could not come up with a test) but just by inspecting the code I thought it's very suspicious.

But I did remove the assert(!exc_state.is_reraise) assert because it got hit in a legitimate case,
(c++ exception got rethrowen in the llvm tier, cought in our c++ code and rethrowen because of api mismatch. With no python code in between.)

Reenable the 'extra' tests

I don't know what the reason is, but it's tripping up cffi's test suite.

Extract the logic from DEFAULT_CLASS_SIMPLE

One small change for numpy performance

merge the missing merge commits (mostly cosmetic change)

so that it can be used in more places.  Looking at pyxl_bench2_10x,
most of the calls to PyType_GenericAlloc are from the dict and list
iterator classes, which don't use DEFAULT_CLASS_SIMPLE (or DEFAULT_CLASS)
since they use the same C++ class with multiple Python classes.  So
by extracting out the core of that function, it's now usable by those
other classes.

Also convert some things to DEFAULT_CLASS_SIMPLE while we're at it.

- support CPython
- don't blow away the checkout each time

Numpy was hitting this a lot

I love optimizing things we haven't approached before.  This small change
improved numpy.test() performance by 20%.

some minor NumPy fixing

Fix remaining "check refcounting" assertions

Conflicts:
	src/codegen/compvars.cpp

Remove numpy submodule

clone numpy with 1.11.0 tag from github,
and adjust the numpy test file.

Some misc performance optimizations

They were all in code that is now dead, so I spent some time
verifying that and cleaning it up.

Make rearrangeArgs take a callback instead passing back values

thanks Marius for the tip

add tuple free list and don't update boxed frame on exit when it's not used

My hunch is that code density is more important than avoiding
ome of the `if (rewrite_args)` checks.

Also add some hacks to get rid of the func-name-getter-as-lambda,
so we don't need to templatize on that either.

Results of this commit are kind of mixed:

       django_template3_10x.py            13.6s (2)            13.8s (2)  +1.4%
 sqlalchemy_imperative2_10x.py            18.8s (2)            19.0s (2)  +1.2%
            pyxl_bench2_10x.py            10.7s (2)            10.1s (2)  -5.1%
                       geomean                14.0s                13.8s  -0.9%