try to work around a Py_FatalError crash in latest Py3.6 apparently due to a RuntimeWarning during garbage collection

Replace old build_ext with new cythonize(...) version.

This closes #1433.

p_f_string_expr produced warning: implicit conversion loses integer precision: 'long' to 'Py_UCS4' (aka 'unsigned int') [-Wshorten-64-to-32]

Closes #1458.

Support dependencies in conditional compilation

Adds support for simple FakeReference equality testing.

setup.py shouldn't write arbitrarily to stdout (especially when passed display options)

The old build_ext is now named old_build_ext, replaced with the one from Cython/Build.

In general it's best for actions performed in `setup.py` to be deferred until the command to which they are relevant is actually run.  For example most of what `compile_cython_modules` does should be deferred until finalizing the `build_ext` command.  But as a simpler workaround, just ensure that anything it prints is to stderr.

Otherwise this breaks certain assumptions, such as that `./setup.py --name` will print (on stdout) the distribution name (and nothing else), and likewise for `./setup.py --version`.

Cython.Build brings in cythonize, which is not in a Py3.2 compatible file.

Fix overriding of cdef by cpdef method in .pxd file

Repair calls to fused staticmethods : we currently generate the wrong C signature for them (first arg becomes 'self' arg), so this change works around that by really passing the first argument as 'self'.
Eventually, ths signature should be fixed instead.

restrict "__dict__" property generation to declared "__dict__" attributes and ignore everything else

Closes #531.