WIP: First stop towards python bindings

This is a very rough first stab at compiling CFFI Python bindings
for deltachat-core.

python/setup.py

@@ -0,0 +1,22 @@
+import setuptools
+
+
+setuptools.setup(
+    name='deltachat',
+    version='0.1',
+    description='Python bindings for deltachat-core using CFFI',
+    author='Delta Chat contributors',
+    setup_requires=['cffi>=1.0.0'],
+    install_requires=['cffi>=1.0.0'],
+    packages=setuptools.find_packages('src'),
+    package_dir={'': 'src'},
+    cffi_modules=['src/deltachat/_build.py:ffibuilder'],
+    classifiers=[
+        'Development Status :: 3 - Alpha',
+        'Intended Audience :: Developers',
+        'License :: OSI Approved :: GNU General Public License (GPL)',
+        'Programming Language :: Python :: 3',
+        'Topic :: Communications :: Email',
+        'Topic :: Software Development :: Libraries',
+    ],
+)

python/src/deltachat/_build.py

@@ -0,0 +1,23 @@
+import subprocess
+import tempfile
+
+import cffi
+
+
+ffibuilder = cffi.FFI()
+ffibuilder.set_source(
+    'deltachat.capi',
+    """
+    #include <deltachat/mrmailbox.h>
+    """,
+    libraries=['deltachat'],
+)
+with tempfile.NamedTemporaryFile(mode='r') as fp:
+    proc = subprocess.run(['gcc', '-E', '-o', fp.name, '-DPY_CFFI=1',
+                           '../src/mrmailbox.h'])
+    proc.check_returncode()
+    ffibuilder.cdef(fp.read())
+
+
+if __name__ == '__main__':
+    ffibuilder.compile(verbose=True)